Dado un entero n, encuentra si es una potencia de 4 o no.
Ejemplo :
Input : 16 Output : 16 is a power of 4 Input : 20 Output : 20 is not a power of 4
Le recomendamos encarecidamente que haga clic aquí y lo practique antes de pasar a la solución.
1. Usando el método de registro incorporado:
Lleve el logaritmo del número dado a la base 4 y luego eleve 4 a este resultado. Si la salida es igual a n, entonces el número dado es una potencia de 4, de lo contrario no.
C++
// C++ program to find whether a given
// number is a power of 4 or not
#include<bits/stdc++.h>
using namespace std;
#define bool int
class GFG
{
/* Function to check if x is power of 4*/
public : bool isPowerOfFour(int n)
{
if(n == pow(4, (log(n)/log(4))))
return true;
return false;
}
};
/*Driver code*/
int main()
{
GFG g;
int test_no = 64;
if(g.isPowerOfFour(test_no))
cout << test_no << " is a power of 4";
else
cout << test_no << " is not a power of 4";
}
// This code is contributed by Code_r
Java
// Java program to find whether a given number is a power of
// 4 or not
import java.io.*;
class GFG {
// Function to check if x is a power of 4
public boolean isPowerOfFour(int n)
{
if (n== (int)Math.pow(4, (Math.log(n) / Math.log(4)))) {
return true;
}
return false;
}
public static void main(String[] args)
{
GFG g = new GFG();
int test_no = 64;
if (g.isPowerOfFour(test_no)) {
System.out.print(test_no + " is a power of 4 ");
}
else {
System.out.print(test_no
+ " is not a power of 4");
}
}
}
// This code is contributed by lokesh (lokeshmvs21).
C#
// C# program to find whether a given number is a power of 4
// or not.
using System;
public class GFG {
// Function to check if x is power of 4
public bool isPowerOfFour(int n)
{
if (n == Math.Pow(4, (Math.Log(n) / Math.Log(4)))) {
return true;
}
return false;
}
static public void Main()
{
// Code
GFG g = new GFG();
int test_no = 64;
if (g.isPowerOfFour(test_no)) {
Console.Write(test_no + " is a power of 4");
}
else {
Console.Write(test_no + " is not a power of 4");
}
}
}
// This code is contributed by lokesh (lokeshmvs21)
Python3
# Python program to find whether a given number is a power of 4 or not. import math # Function to check if x is power of 4 def isPowerOfFour(n): if (n == pow(4, (math.log(n)/math.log(4)))): return True return False test_no = 64 if(isPowerOfFour(test_no)): print(test_no, ' is a power of 4') else: print(test_no, ' is not a power of 4') # This code is contributed by lokesh (lokeshmvs21).
Producción
64 is a power of 4
2. Otra solución es seguir dividiendo el número por 4, es decir, hacer n = n/4 iterativamente. En cualquier iteración, si n%4 se vuelve distinto de cero y n no es 1, entonces n no es una potencia de 4, de lo contrario, n es una potencia de 4.
C++
// C++ program to find whether a given
// number is a power of 4 or not
#include<iostream>
using namespace std;
#define bool int
class GFG
{
/* Function to check if x is power of 4*/
public : bool isPowerOfFour(int n)
{
if(n == 0)
return 0;
while(n != 1)
{
if(n % 4 != 0)
return 0;
n = n / 4;
}
return 1;
}
};
/*Driver code*/
int main()
{
GFG g;
int test_no = 64;
if(g.isPowerOfFour(test_no))
cout << test_no << " is a power of 4";
else
cout << test_no << "is not a power of 4";
getchar();
}
// This code is contributed by SoM15242
C
#include<stdio.h>
#define bool int
/* Function to check if x is power of 4*/
bool isPowerOfFour(int n)
{
if(n == 0)
return 0;
while(n != 1)
{
if(n % 4 != 0)
return 0;
n = n / 4;
}
return 1;
}
/*Driver program to test above function*/
int main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
printf("%d is a power of 4", test_no);
else
printf("%d is not a power of 4", test_no);
getchar();
}
Java
// Java code to check if given
// number is power of 4 or not
class GFG {
// Function to check if
// x is power of 4
static int isPowerOfFour(int n)
{
if(n == 0)
return 0;
while(n != 1)
{
if(n % 4 != 0)
return 0;
n = n / 4;
}
return 1;
}
// Driver program
public static void main(String[] args)
{
int test_no = 64;
if(isPowerOfFour(test_no) == 1)
System.out.println(test_no +
" is a power of 4");
else
System.out.println(test_no +
"is not a power of 4");
}
}
// This code is contributed
// by prerna saini
Python3
# Python3 program to check if given # number is power of 4 or not # Function to check if x is power of 4 def isPowerOfFour(n): if (n == 0): return False while (n != 1): if (n % 4 != 0): return False n = n // 4 return True # Driver code test_no = 64 if(isPowerOfFour(64)): print(test_no, 'is a power of 4') else: print(test_no, 'is not a power of 4') # This code is contributed by Danish Raza
C#
// C# code to check if given
// number is power of 4 or not
using System;
class GFG {
// Function to check if
// x is power of 4
static int isPowerOfFour(int n)
{
if (n == 0)
return 0;
while (n != 1) {
if (n % 4 != 0)
return 0;
n = n / 4;
}
return 1;
}
// Driver code
public static void Main()
{
int test_no = 64;
if (isPowerOfFour(test_no) == 1)
Console.Write(test_no +
" is a power of 4");
else
Console.Write(test_no +
" is not a power of 4");
}
}
// This code is contributed by Sam007
PHP
<?php
// PHP code to check if given
// number is power of 4 or not
// Function to check if
// x is power of 4
function isPowerOfFour($n)
{
if($n == 0)
return 0;
while($n != 1)
{
if($n % 4 != 0)
return 0;
$n = $n / 4;
}
return 1;
}
// Driver Code
$test_no = 64;
if(isPowerOfFour($test_no))
echo $test_no," is a power of 4";
else
echo $test_no," is not a power of 4";
// This code is contributed by Rajesh
?>
Javascript
<script>
/* Function to check if x is power of 4*/
function isPowerOfFour( n)
{
if(n == 0)
return false;
while(n != 1)
{
if(n % 4 != 0)
return false;
n = n / 4;
}
return true;
}
/*Driver program to test above function*/
let test_no = 64;
if(isPowerOfFour(test_no))
document.write(test_no+" is a power of 4");
else
document.write(test_no+" is not a power of 4");
// This code is contributed by gauravrajput1
</script>
Producción
64 is a power of 4
Complejidad de tiempo: O (log 4 n)
Espacio auxiliar: O(1)
3. Un número n es una potencia de 4 si se cumplen las siguientes condiciones.
a) Solo hay un bit establecido en la representación binaria de n (o n es una potencia de 2)
b) La cuenta de bits cero antes de que el (único) bit establecido sea par.
Por ejemplo, 16 (10000) es la potencia de 4 porque solo hay un bit establecido y un conteo de 0 antes de que el bit establecido sea 4, que es par.
Gracias a Geek4u por sugerir el enfoque y proporcionar el código.
C++
// C++ program to check
// if given number is
// power of 4 or not
#include<bits/stdc++.h>
using namespace std;
bool isPowerOfFour(unsigned int n)
{
int count = 0;
/*Check if there is only one bit set in n*/
if ( n && !(n&(n-1)) )
{
/* count 0 bits before set bit */
while(n > 1)
{
n >>= 1;
count += 1;
}
/*If count is even then
return true else false*/
return (count%2 == 0)? 1 :0;
}
/* If there are more than 1 bit set
then n is not a power of 4*/
return 0;
}
/*Driver code*/
int main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
cout << test_no << " is a power of 4" ;
else
cout << test_no << " is not a power of 4";
}
// This code is contributed by Shivi_Aggarwal
C
#include<stdio.h>
#define bool int
bool isPowerOfFour(unsigned int n)
{
int count = 0;
/*Check if there is only one bit set in n*/
if ( n && !(n&(n-1)) )
{
/* count 0 bits before set bit */
while(n > 1)
{
n >>= 1;
count += 1;
}
/*If count is even then return true else false*/
return (count%2 == 0)? 1 :0;
}
/* If there are more than 1 bit set
then n is not a power of 4*/
return 0;
}
/*Driver program to test above function*/
int main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
printf("%d is a power of 4", test_no);
else
printf("%d is not a power of 4", test_no);
getchar();
}
Java
// Java program to check
// if given number is
// power of 4 or not
import java.io.*;
class GFG
{
static int isPowerOfFour(int n)
{
int count = 0;
/*Check if there is
only one bit set in n*/
int x = n & (n - 1);
if ( n > 0 && x == 0)
{
/* count 0 bits
before set bit */
while(n > 1)
{
n >>= 1;
count += 1;
}
/*If count is even
then return true
else false*/
return (count % 2 == 0) ? 1 : 0;
}
/* If there are more than
1 bit set then n is not a
power of 4*/
return 0;
}
// Driver Code
public static void main(String[] args)
{
int test_no = 64;
if(isPowerOfFour(test_no)>0)
System.out.println(test_no +
" is a power of 4");
else
System.out.println(test_no +
" is not a power of 4");
}
}
// This code is contributed by mits
Python3
# Python3 program to check if given # number is power of 4 or not # Function to check if x is power of 4 def isPowerOfFour(n): count = 0 # Check if there is only one # bit set in n if (n and (not(n & (n - 1)))): # count 0 bits before set bit while(n > 1): n >>= 1 count += 1 # If count is even then return # true else false if(count % 2 == 0): return True else: return False # Driver code test_no = 64 if(isPowerOfFour(64)): print(test_no, 'is a power of 4') else: print(test_no, 'is not a power of 4') # This code is contributed by Danish Raza
C#
// C# program to check if given
// number is power of 4 or not
using System;
class GFG {
static int isPowerOfFour(int n)
{
int count = 0;
/*Check if there is only one bit
set in n*/
int x = n & (n-1);
if ( n > 0 && x == 0)
{
/* count 0 bits before set bit */
while(n > 1)
{
n >>= 1;
count += 1;
}
/*If count is even then return
true else false*/
return (count % 2 == 0) ? 1 : 0;
}
/* If there are more than 1 bit set
then n is not a power of 4*/
return 0;
}
/*Driver program to test above function*/
static void Main()
{
int test_no = 64;
if(isPowerOfFour(test_no)>0)
Console.WriteLine("{0} is a power of 4",
test_no);
else
Console.WriteLine("{0} is not a power of 4",
test_no);
}
}
// This Code is Contributed by mits
PHP
<?php
function isPowerOfFour($n)
{
$count = 0;
/*Check if there is only one bit set in n*/
if ( $n && !($n&($n-1)) )
{
/* count 0 bits before set bit */
while($n > 1)
{
$n >>= 1;
$count += 1;
}
/*If count is even then return true else false*/
return ($count%2 == 0)? 1 :0;
}
/* If there are more than 1 bit set
then n is not a power of 4*/
return 0;
}
/*Driver program to test above function*/
$test_no = 64;
if(isPowerOfFour($test_no))
echo $test_no, " is a power of 4";
else
echo $test_no, " not is a power of 4";
#This Code is Contributed by Ajit
?>
Javascript
<script>
// javascript program to check
// if given number is
// power of 4 or not
function isPowerOfFour( n)
{
let count = 0;
/*Check if there is only one bit set in n*/
if ( n && !(n&(n-1)) )
{
/* count 0 bits before set bit */
while(n > 1)
{
n >>= 1;
count += 1;
}
/*If count is even then
return true else false*/
return (count%2 == 0)? 1 :0;
}
/* If there are more than 1 bit set
then n is not a power of 4*/
return 0;
}
/*Driver code*/
let test_no = 64;
if(isPowerOfFour(test_no))
document.write( test_no +" is a power of 4" );
else
document.write(test_no + " is not a power of 4");
// This code contributed by aashish1995
</script>
Producción
64 is a power of 4
Complejidad de tiempo: O (log 4 n)
Espacio Auxiliar: O(1)
4. Un número n es una potencia de 4 si se cumplen las siguientes condiciones.
a) Solo hay un bit establecido en la representación binaria de n (o n es una potencia de 2)
b) Los bits no AND(&) ninguna parte del patrón 0xAAAAAAAA
Por ejemplo: 16 (10000) es una potencia de 4 porque solo hay un bit establecido y 0x10 y 0xAAAAAAAA es cero.
Gracias a Sarthak Sahu por sugerir el enfoque.
C++
// C++ program to check
// if given number is
// power of 4 or not
#include<bits/stdc++.h>
using namespace std;
bool isPowerOfFour(unsigned int n)
{
return n !=0 && ((n&(n-1)) == 0) && !(n & 0xAAAAAAAA);
}
/*Driver code*/
int main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
cout << test_no << " is a power of 4" ;
else
cout << test_no << " is not a power of 4";
}
C
// C program to check
// if given number is
// power of 4 or not
#include<stdio.h>
#define bool int
bool isPowerOfFour(unsigned int n)
{
return n != 0 && ((n&(n-1)) == 0) && !(n & 0xAAAAAAAA);
}
/*Driver program to test above function*/
int main() {
int test_no = 64;
if(isPowerOfFour(test_no))
printf("%d is a power of 4", test_no);
else
printf("%d is not a power of 4", test_no);
getchar();
}
Java
// Java program to check
// if given number is
// power of 4 or not
import java.io.*;
class GFG {
static boolean isPowerOfFour(int n) {
return n != 0 && ((n&(n-1)) == 0) && (n & 0xAAAAAAAA) == 0;
}
// Driver Code
public static void main(String[] args) {
int test_no = 64;
if(isPowerOfFour(test_no))
System.out.println(test_no +
" is a power of 4");
else
System.out.println(test_no +
" is not a power of 4");
}
}
Python3
# Python3 program to check # if given number is # power of 4 or not def isPowerOfFour(n): return (n != 0 and ((n & (n - 1)) == 0) and not(n & 0xAAAAAAAA)); # Driver code test_no = 64; if(isPowerOfFour(test_no)): print(test_no ,"is a power of 4"); else: print(test_no , "is not a power of 4"); # This code contributed by Rajput-Ji
C#
// C# program to check
// if given number is
// power of 4 or not
using System;
class GFG
{
static bool isPowerOfFour(int n)
{
return n != 0 && ((n&(n-1)) == 0) &&
(n & 0xAAAAAAAA) == 0;
}
// Driver Code
static void Main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
Console.WriteLine("{0} is a power of 4",
test_no);
else
Console.WriteLine("{0} is not a power of 4",
test_no);
}
}
// This code is contributed by mohit kumar 29
Javascript
<script>
// C++ program to check
// if given number is
// power of 4 or not
function isPowerOfFour( n)
{
return n !=0 && ((n&(n-1)) == 0) && !(n & 0xAAAAAAAA);
}
/*Driver code*/
test_no = 64;
if(isPowerOfFour(test_no))
document.write(test_no + " is a power of 4");
else
document.write(test_no + " is not a power of 4");
//This code is contributed by simranarora5sos
</script>
Producción
64 is a power of 4
Complejidad de tiempo: O (log 4 n)
Espacio auxiliar: O(1)
¿Por qué 0xAAAAAAAA? Esto se debe a que la representación de bits es de potencias de 2 que no son de 4. Como 2, 8, 32, etc.
5. Un número será una potencia de 4 si floor(log4(num))=ceil(log4(num) porque log4 de un número que es una potencia de 4 siempre será un número entero.
A continuación se muestra la implementación del enfoque anterior.
C++
// C++ program to check
// if given number is
// power of 4 or not
#include<bits/stdc++.h>
using namespace std;
float logn(int n, int r)
{
return log(n) / log(r);
}
bool isPowerOfFour(int n)
{
//0 is not considered as a power
//of 4
if(n == 0)
return false;
return floor(logn(n,4))==ceil(logn(n,4));
}
/*Driver code*/
int main()
{
int test_no = 64;
if(isPowerOfFour(test_no))
cout << test_no << " is a power of 4" ;
else
cout << test_no << " is not a power of 4";
return 0;
}
Java
// Java program to check
// if given number is
// power of 4 or not
import java.util.*;
class GFG{
static double logn(int n,
int r)
{
return Math.log(n) /
Math.log(r);
}
static boolean isPowerOfFour(int n)
{
// 0 is not considered
// as a power of 4
if (n == 0)
return false;
return Math.floor(logn(n, 4)) ==
Math.ceil(logn(n, 4));
}
// Driver code
public static void main(String[] args)
{
int test_no = 64;
if (isPowerOfFour(test_no))
System.out.print(test_no +
" is a power of 4");
else
System.out.print(test_no +
" is not a power of 4");
}
}
// This code is contributed by Amit Katiyar
Python3
# Python3 program to check # if given number is # power of 4 or not import math def logn(n, r): return math.log(n) / math.log(r) def isPowerOfFour(n): # 0 is not considered # as a power of 4 if (n == 0): return False return (math.floor(logn(n, 4)) == math.ceil(logn(n, 4))) # Driver code if __name__ == '__main__': test_no = 64 if (isPowerOfFour(test_no)): print(test_no, " is a power of 4") else: print(test_no, " is not a power of 4") # This code is contributed by Amit Katiyar
C#
// C# program to check
// if given number is
// power of 4 or not
using System;
class GFG{
static double logn(int n,
int r)
{
return Math.Log(n) /
Math.Log(r);
}
static bool isPowerOfFour(int n)
{
// 0 is not considered
// as a power of 4
if (n == 0)
return false;
return Math.Floor(logn(n, 4)) ==
Math.Ceiling(logn(n, 4));
}
// Driver code
public static void Main(String[] args)
{
int test_no = 64;
if (isPowerOfFour(test_no))
Console.Write(test_no +
" is a power of 4");
else
Console.Write(test_no +
" is not a power of 4");
}
}
// This code is contributed by 29AjayKumar
Javascript
<script>
// javascript program to check
// if given number is
// power of 4 or not
function logn( n, r)
{
return Math.log(n) / Math.log(r);
}
function isPowerOfFour( n)
{
//0 is not considered as a power
//of 4
if(n == 0)
return false;
return Math.floor(logn(n,4))==Math.ceil(logn(n,4));
}
/*Driver code*/
let test_no = 64;
if(isPowerOfFour(test_no))
document.write(test_no + " is a power of 4") ;
else
document.write( test_no + " is not a power of 4");
// This code contributed by gauravrajput1
</script>
Producción
64 is a power of 4
Complejidad de tiempo: O (log 4 n)
Espacio Auxiliar: O(1)
6. Usando Log y sin usar ceil (Oneliner)
Podemos calcular fácilmente sin usar ceil comprobando que el logaritmo del número base 4 elevado a 4 es igual a ese número
C++
// C++ program to check
// if given number is
// power of 4 or not
#include <bits/stdc++.h>
using namespace std;
int isPowerOfFour(int n)
{
return (n > 0 and pow(4, int(log2(n) /
log2(4))) == n);
}
// Driver code
int main()
{
int test_no = 64;
if (isPowerOfFour(test_no))
cout << test_no << " is a power of 4";
else
cout << test_no << " is not a power of 4";
return 0;
}
// This code is contributed by ukasp
Java
// Java program to check
// if given number is
import java.io.*;
class GFG{
static boolean isPowerOfFour(int n)
{
return (n > 0 && Math.pow(
4, (int)((Math.log(n) /
Math.log(2)) /
(Math.log(4) /
Math.log(2)))) == n);
}
// Driver code
public static void main(String[] args)
{
int test_no = 64;
if (isPowerOfFour(test_no))
System.out.println(test_no +
" is a power of 4");
else
System.out.println(test_no +
" is not a power of 4");
}
}
// This code is contributed by rag2127
Python3
# Python3 program to check # if given number is # power of 4 or not import math def isPowerOfFour(n): return (n > 0 and 4**int(math.log(n, 4)) == n) # Driver code if __name__ == '__main__': test_no = 64 if (isPowerOfFour(test_no)): print(test_no, " is a power of 4") else: print(test_no, " is not a power of 4") # This code is contributed by vikkycirus
C#
// C# program to check
// if given number is
using System;
class GFG
{
static Boolean isPowerOfFour(int n)
{
return (n > 0 && Math.Pow(
4, (int)((Math.Log(n) /
Math.Log(2)) /
(Math.Log(4) /
Math.Log(2)))) == n);
}
// Driver code
public static void Main(String[] args)
{
int test_no = 64;
if (isPowerOfFour(test_no))
Console.WriteLine(test_no +
" is a power of 4");
else
Console.WriteLine(test_no +
" is not a power of 4");
}
}
// This code is contributed by shivanisinghss2110
Javascript
<script>
// Javascript program to check
// if given number is
// power of 4 or not
function isPowerOfFour(n)
{
return (n > 0 && Math.pow(4, (Math.log2(n) /
Math.log2(4)) == n));
}
// Driver code
let test_no = 64;
if (isPowerOfFour(test_no))
document.write(test_no +
" is a power of 4");
else
document.write(test_no +
" is not a power of 4");
// This code is contributed by avijitmondal1998
</script>
Producción
64 is a power of 4
Complejidad de tiempo: O (log 4 n)
Espacio Auxiliar: O(1)
7. Un número ‘n’ es una potencia de 4 si –
a) es un cuadrado perfecto
b) Es una potencia de dos
A continuación se muestra la implementación de la idea anterior.
C++
// C++ program to check if given number is power of 4 or not
#include <bits/stdc++.h>
using namespace std;
// Function to check perfect square
bool isPerfectSqaure(int n)
{
int x = sqrt(n);
return (x * x == n);
}
bool isPowerOfFour(int n)
{
// If n <= 0, it is not the power of four
if (n <= 0)
return false;
// Check whether 'n' is a perfect square or not
if (!isPerfectSqaure(n))
return false;
// If 'n' is the perfect square Check for the second
// condition i.e. 'n' must be power of two
return !(n & (n - 1));
}
/*Driver code*/
int main()
{
int test_no = 64;
if (isPowerOfFour(test_no))
cout << test_no << " is a power of 4";
else
cout << test_no << " is not a power of 4";
return 0;
}
// This code is contributed by Aditya Kumar (adityakumar129)
C
// C program to check if given number is power of 4 or not
#include <math.h>
#include <stdbool.h>
#include <stdio.h>
// Function to check perfect square
bool isPerfectSqaure(int n)
{
int x = sqrt(n);
return (x * x == n);
}
bool isPowerOfFour(int n)
{
// If n <= 0, it is not the power of four
if (n <= 0)
return false;
// Check whether 'n' is a perfect square or not
if (!isPerfectSqaure(n))
return false;
// If 'n' is the perfect square Check for the second
// condition i.e. 'n' must be power of two
return !(n & (n - 1));
}
/*Driver code*/
int main()
{
int test_no = 64;
if (isPowerOfFour(test_no))
printf("%d is a power of 4", test_no);
else
printf("%d is not a power of 4", test_no);
return 0;
}
// This code is contributed by Aditya Kumar (adityakumar129)
Java
// Java program to check
// if given number is
// power of 4 or not
import java.util.*;
class GFG {
// Function to check perfect square
static boolean isPerfectSqaure(int n) {
int x = (int) Math.sqrt(n);
return (x * x == n);
}
static boolean isPowerOfFour(int n)
{
// If n <= 0, it is not the power of four
if (n <= 0)
return false;
// Check whether 'n' is a perfect square or not
if (!isPerfectSqaure(n))
return false;
// If 'n' is the perfect square
// Check for the second condition i.e. 'n' must be power of two
return (n & (n - 1)) != 1 ? true : false;
}
/* Driver code */
public static void main(String[] args) {
int test_no = 64;
if (isPowerOfFour(test_no))
System.out.print(test_no + " is a power of 4");
else
System.out.print(test_no + " is not a power of 4");
}
}
// This code is contributed by gauravrajput1
Python3
# Python program to check # if given number is # power of 4 or not # Function to check perfect square # import the math module import math def isPerfectSqaure(n): x = math.sqrt(n) return (x*x == n) def isPowerOfFour(n): # If n <= 0, it is not the power of four if(n <= 0): return False # Check whether 'n' is a perfect square or not if(isPerfectSqaure(n)): return False # If 'n' is the perfect square # Check for the second condition i.e. 'n' must be power of two return (n & (n - 1)) # Driver code test_no = 64 if(isPowerOfFour(test_no)): print(test_no ," is a power of 4") else: print(test_no ," is not a power of 4") # This code is contributed by shivanisinghss2110
C#
// C# program to check
// if given number is
// power of 4 or not
using System;
public class GFG {
// Function to check perfect square
static bool isPerfectSqaure(int n) {
int x = (int) Math.Sqrt(n);
return (x * x == n);
}
static bool isPowerOfFour(int n)
{
// If n <= 0, it is not the power of four
if (n <= 0)
return false;
// Check whether 'n' is a perfect square or not
if (!isPerfectSqaure(n))
return false;
// If 'n' is the perfect square
// Check for the second condition i.e. 'n' must be power of two
return (n & (n - 1)) != 1 ? true : false;
}
/* Driver code */
public static void Main(String[] args) {
int test_no = 64;
if (isPowerOfFour(test_no))
Console.Write(test_no + " is a power of 4");
else
Console.Write(test_no + " is not a power of 4");
}
}
// This code is contributed by umadevi9616
Javascript
<script>
// JavaScript program to check
// if given number is
// power of 4 or not
// Function to check perfect square
function isPerfectSqaure( n) {
var x = Math.sqrt(n);
return (x * x == n);
}
function isPowerOfFour(n)
{
// If n <= 0, it is not the power of four
if (n <= 0)
return false;
// Check whether 'n' is a perfect square or not
if (!isPerfectSqaure(n))
return false;
// If 'n' is the perfect square
// Check for the second condition i.e. 'n' must be power of two
return (n & (n - 1)) != 1 ? true : false;
}
/* Driver code */
var test_no = 64;
if (isPowerOfFour(test_no))
document.write(test_no + " is a power of 4");
else
document.write(test_no + " is not a power of 4");
// This code is contributed by shivanisinghss2110
</script>
Producción
64 is a power of 4
Complejidad del tiempo: O(log 2 n)
Espacio Auxiliar: O(1)
Escriba comentarios si encuentra que alguno de los códigos/algoritmos anteriores es incorrecto o encuentra otras formas de resolver el mismo problema.
Publicación traducida automáticamente
Artículo escrito por GeeksforGeeks-1 y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA