Dado un número, comprueba si es par o impar.
Ejemplos:
Input: n = 11 Output: Odd Input: n = 10 Output: Even
Método 1: Usando Loop.
La idea es comenzar con una variable de bandera booleana como verdadera y cambiarla n veces. Si la variable indicadora recupera el valor original (que es verdadero), entonces n es par. De lo contrario, n es falsa.
A continuación se muestra la implementación de esta idea.
C++
// A simple C++ program to check for
// even or odd
#include <iostream>
using namespace std;
// Returns true if n is even, else odd
bool isEven(int n)
{
bool isEven = true;
for (int i=1; i <= n; i++)
isEven = !isEven;
return isEven;
}
// Driver code
int main()
{
int n = 101;
isEven(n) ? cout << "Even" : cout << "Odd";
return 0;
}
Java
// A simple Java program to
// check for even or odd
class GFG {
// Returns true if n
// is even, else odd
static boolean isEven(int n)
{
boolean isEven = true;
for (int i = 1; i <= n; i++)
isEven = !isEven;
return isEven;
}
// Driver Code
public static void main(String args[])
{
int n = 101;
if(isEven(n))
System.out.println("Even");
else
System.out.println("Odd");
}
}
// This code is contributed by Sam007
Python3
# A simple Python program to
# check for even or odd
# Returns true if n is even,
# else odd
def isEven(n):
isEven = True;
for i in range(1, n+1):
if isEven == True:
isEven = False;
else:
isEven = True;
return isEven;
# Driver code
n = 101;
if isEven(n) == True:
print ("Even");
else:
print ("Odd");
# This code is contributed by
# Manish Shaw (manishshaw1)
C#
// A simple C# program to check for
// even or odd
using System;
public class GFG {
// Returns true if n is even,
// else odd
static bool isEven(int n)
{
bool isEven = true;
for (int i = 1; i <= n; i++)
isEven = !isEven;
return isEven;
}
// Driver code
public static void Main()
{
int n = 101;
if(isEven(n))
Console.Write("Even");
else
Console.Write("Odd");
}
}
// This code is contributed by Sam007.
PHP
<?php
// A simple PHP program to check for
// even or odd
// Returns true if n is even,
// else odd
function isEven($n)
{
$isEven = true;
for ($i = 1; $i <= $n; $i++)
$isEven = !$isEven;
return $isEven;
}
// Driver code
$n = 101;
$is=isEven($n) ? "Even" : "Odd";
echo "$is"
// This code is contributed by ajit
?>
Javascript
<script>
// A simple Javascript program to check
// for even or odd
// Returns true if n is even,
// else odd
function isEven(n)
{
let isEven = true;
for(let i = 1; i <= n; i++)
isEven = !isEven;
return isEven;
}
// Driver code
let n = 101;
if (isEven(n))
document.write("Even");
else
document.write("Odd");
// This code is contributed by mukesh07
</script>
Producción:
Odd
Complejidad de tiempo : O(n)
Espacio Auxiliar: O(1)
Método 2: Multiplique y divida por 2. Divida el número por 2 y multiplique por 2 si el resultado es el mismo que el ingresado, entonces es un número par; de lo contrario, es un número impar.
C++
// A simple C++ program to check for
// even or odd
#include <iostream>
using namespace std;
// Returns true if n is even, else odd
bool isEven(int n)
{
// Return true if n/2 does not result
// in a float value.
return ((n / 2) * 2 == n);
}
// Driver code
int main()
{
int n = 101;
isEven(n) ? cout << "Even" : cout << "Odd";
return 0;
}
Java
// A simple Java program
// to check for even or odd
class GFG {
// Returns true if n
// is even, else odd
static boolean isEven(int n)
{
// Return true if
// n/2 does not result
// in a float value.
return ((n / 2) * 2 == n);
}
// Driver code
public static void main(String[] args)
{
int n = 101;
if(isEven(n) != false)
System.out.print( "Even" );
else
System.out.print( "Odd" );
}
}
// This code is contributed by
// Smitha Dinesh Semwal.
Python3
# A simple Python 3 program
# to check for even or odd
# Returns true if n
# is even, else odd
def isEven(n):
# Return true if
# n/2 does not result
# in a float value.
return (int(n / 2) * 2 == n)
# Driver code
n = 101
if(isEven(n) != False):
print("Even")
else:
print("Odd")
# This code is contributed by
# Smitha Dinesh Semwal.
C#
// A simple C# program
// to check for even or odd
using System;
class GFG {
// Returns true if n
// is even, else odd
static bool isEven(int n)
{
// Return true if
// n/2 does not result
// in a float value.
return ((n / 2) * 2 == n);
}
// Driver code
public static void Main(String[] args)
{
int n = 101;
if(isEven(n) != false)
Console.Write("Even");
else
Console.Write("Odd");
}
}
// This code is contributed by
// Smitha Dinesh Semwal.
PHP
<?php
// A simple PHP program to
// check for even or odd
// Returns true if n
// is even, else odd
function isEven($n)
{
// Return true if n/2
// does not result
// in a float value.
return ((int)($n / 2) * 2 == $n);
}
// Driver code
$n = 101;
if(isEven($n))
echo ("Even");
else
echo ("Odd");
// This code is contributed by
// Manish Shaw (manishshaw1)
?>
Javascript
<script>
// A simple Javascript program to
// check for even or odd
// Returns true if n is even,
// else odd
function isEven(n)
{
// Return true if n/2 does not result
// in a float value.
return (parseInt(n / 2, 10) * 2 == n);
}
// Driver code
let n = 101;
isEven(n) ? document.write("Even") :
document.write("Odd");
// This code is contributed by divyeshrabadiya07
</script>
Producción :
Odd
Complejidad de tiempo : O(1)
Espacio Auxiliar: O(1)
Método 3: Usar el operador bit a bit &.
Una mejor solución es utilizar operadores bit a bit. Necesitamos verificar si el último bit es 1 o no. Si el último bit es 1, el número es impar; de lo contrario, siempre es par.
Explicación:
input : 5 // odd 00000101 & 00000001 -------------- 00000001 -------------- input : 8 //even 00001000 & 00000001 -------------- 00000000 --------------
A continuación se muestra la implementación de la idea.
C++
// A simple C++ program to check for
// even or odd
#include <iostream>
using namespace std;
// Returns true if n is even, else odd
bool isEven(int n)
{
// n&1 is 1, then odd, else even
return (!(n & 1));
}
// Driver code
int main()
{
int n = 101;
isEven(n) ? cout << "Even" : cout << "Odd";
return 0;
}
Java
// A simple Java program to check for
// even or odd
import java.io.*;
import java.util.*;
public class GFG {
// Returns 0 if n
// is even, else odd
static int isEven(int n)
{
// n&1 is 1, then
// odd, else even
return (n & 1);
}
// Driver code
public static void main(String args[])
{
int n = 101;
if(isEven(n)==0)
System.out.print("Even");
else
System.out.print("Odd");
}
}
// This code is contributed
// by Manish Shaw (manishshaw1)
Python3
# A simple Python program to
# check for even or odd
# Returns 0 if n
# is even, else odd
def isEven(n) :
# n&1 is 1, then
# odd, else even
return (n & 1);
# Driver code
n = 101;
if(isEven(n) == 0) :
print ("Even");
else :
print ("Odd");
# This code is contributed
# by Manish Shaw (manishshaw1)
C#
// A simple C# program to check for
// even or odd
using System;
using System.Collections.Generic;
class GFG {
// Returns 0 if n
// is even, else odd
static int isEven(int n)
{
// n&1 is 1, then
// odd, else even
return (n & 1);
}
// Driver code
public static void Main()
{
int n = 101;
if(isEven(n)==0)
Console.Write("Even");
else
Console.Write("Odd");
}
}
// This code is contributed
// by Manish Shaw (manishshaw1)
PHP
<?php
// A simple PHP program to
// check for even or odd
// Returns 0 if n
// is even, else odd
function isEven($n)
{
// n&1 is 1, then
// odd, else even
return ($n & 1);
}
// Driver code
$n = 101;
if(isEven($n) == 0)
echo ("Even");
else
echo ("Odd");
// This code is contributed
// by Manish Shaw (manishshaw1)
?>
Javascript
<script>
// A simple Javascript program to check for even or odd
// Returns true if n is even, else odd
function isEven(n)
{
// n&1 is 1, then odd, else even
return (!(n & 1));
}
let n = 101;
isEven(n) ? document.write("Even") : document.write("Odd");
</script>
Producción :
Odd
Complejidad de tiempo : O(1)
Espacio Auxiliar: O(1)
Publicación traducida automáticamente
Artículo escrito por RahulKumarSingh y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA