Número cuadrado perfecto más grande en una array

Posted on by Rudeus Greyrat

Dada una array de n enteros. La tarea es encontrar el número más grande que es un cuadrado perfecto. Escribe -1 si no hay ningún número que sea cuadrado perfecto.
Ejemplos : 
 

Input : arr[] = {16, 20, 25, 2, 3, 10} 
Output : 25
Explanation: 25 is the largest number 
that is a perfect square. 

Input : arr[] = {36, 64, 10, 16, 29, 25| 
Output : 64

Una solución simple es ordenar los elementos y ordenar los n números y comenzar a buscar desde atrás un número cuadrado perfecto usando la función sqrt(). El primer número desde el final que es un número cuadrado perfecto es nuestra respuesta. La complejidad de clasificación es O(n log n) y de la función sqrt() es log n, por lo que en el peor de los casos la complejidad es O(n log n).
Una Solución Eficiente es iterar para todos los elementos en O(n) y comparar cada vez con el elemento máximo, y almacenar el máximo de todos los cuadrados perfectos. 
A continuación se muestra la implementación del enfoque anterior:
 

C++

// CPP program to find the largest perfect
// square number among n numbers
 
#include<iostream>
#include<math.h>
using namespace std;
 
// Function to check if a number
// is perfect square number or not
bool checkPerfectSquare(double n)
{
    // takes the sqrt of the number
    double d = sqrt(n);
 
    // checks if it is a perfect
    // square number
    if (d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
int largestPerfectSquareNumber(int a[], double n)
{
    // stores the maximum of all
    // perfect square numbers
    int maxi = -1;
 
    // Traverse all elements in the array
    for (int i = 0; i < n; i++) {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare(a[i]))
            maxi = max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
int main()
{
    int a[] = { 16, 20, 25, 2, 3, 10 };
 
    double n = sizeof(a) / sizeof(a[0]);
 
    cout << largestPerfectSquareNumber(a, n);
 
    return 0;
}

C

// C program to find the largest perfect
// square number among n numbers
#include <stdio.h>
#include <stdbool.h>
#include <math.h>
 
int max(int a,int b)
{
  int max = a;
  if(max < b)
    max = b;
  return max;
}
 
// Function to check if a number
// is perfect square number or not
bool checkPerfectSquare(double n)
{
    // takes the sqrt of the number
    double d = sqrt(n);
 
    // checks if it is a perfect
    // square number
    if (d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
int largestPerfectSquareNumber(int a[], double n)
{
    // stores the maximum of all
    // perfect square numbers
    int maxi = -1;
 
    // Traverse all elements in the array
    for (int i = 0; i < n; i++) {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare(a[i]))
            maxi = max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
int main()
{
    int a[] = { 16, 20, 25, 2, 3, 10 };
 
    double n = sizeof(a) / sizeof(a[0]);
     
    printf("%d",largestPerfectSquareNumber(a, n));
 
    return 0;
}
 
// This code is contributed by kothavvsaakash.

Java

// Java program to find the largest perfect
// square number among n numbers
import java.lang.Math;
import java.io.*;
 
class GFG {
 
 
// Function to check if a number
// is perfect square number or not
static boolean checkPerfectSquare(double n)
{
    // takes the sqrt of the number
    double d = Math.sqrt(n);
 
    // checks if it is a perfect
    // square number
    if (d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
static int largestPerfectSquareNumber(int a[], double n)
{
    // stores the maximum of all
    // perfect square numbers
    int maxi = -1;
 
    // Traverse all elements in the array
    for (int i = 0; i < n; i++) {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare(a[i]))
            maxi = Math.max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
 
 
    public static void main (String[] args) {
            int []a = { 16, 20, 25, 2, 3, 10 };
 
    double n = a.length;
 
    System.out.println( largestPerfectSquareNumber(a, n));
 
    }
}
// This code is contributed
// by inder_verma..

Python3

# Python3 program to find the largest perfect
# square number among n numbers
 
# from math lib import sqrt()
from math import sqrt
 
# Function to check if a number 
# is perfect square number or not
def checkPerfectSquare(n) :
     
    # takes the sqrt of the number
    d = sqrt(n)
     
    # checks if it is a perfect 
    # square number 
    if d * d == n :
        return True
     
    return False
 
 
# Function to find the largest perfect 
# square number in the array 
def largestPerfectSquareNumber(a, n) :
     
    # stores the maximum of all 
    # perfect square numbers
    maxi = -1
     
    # Traverse all elements in the array
    for i in range(n) :
         
        # store the maximum if current 
        # element is a perfect square 
        if(checkPerfectSquare(a[i])) :
            maxi = max(a[i], maxi)
     
    return maxi
     
         
# Driver code
if __name__ == "__main__" :
     
    a = [16, 20, 25, 2, 3, 10 ]
    n = len(a)
     
    print(largestPerfectSquareNumber(a, n))
     
# This code is contributed by Ryuga

C#

// C# program to find the largest perfect
// square number among n numbers
using System;
class GFG {
 
 
// Function to check if a number
// is perfect square number or not
static bool checkPerfectSquare(double n)
{
    // takes the sqrt of the number
    double d = Math.Sqrt(n);
 
    // checks if it is a perfect
    // square number
    if (d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
static int largestPerfectSquareNumber(int []a, double n)
{
    // stores the maximum of all
    // perfect square numbers
    int maxi = -1;
 
    // Traverse all elements in the array
    for (int i = 0; i < n; i++) {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare(a[i]))
            maxi = Math.Max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
 
 
    public static void Main () {
            int []a = { 16, 20, 25, 2, 3, 10 };
 
    double n = a.Length;
 
    Console.WriteLine( largestPerfectSquareNumber(a, n));
 
    }
}
// This code is contributed
// by inder_verma..

PHP

<?php
// PHP program to find the largest perfect
// square number among n numbers
 
// Function to check if a number
// is perfect square number or not
function checkPerfectSquare($n)
{
    // takes the sqrt of the number
    $d = sqrt($n);
 
    // checks if it is a perfect
    // square number
    if ($d * $d == $n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
function largestPerfectSquareNumber($a, $n)
{
    // stores the maximum of all
    // perfect square numbers
    $maxi = -1;
 
    // Traverse all elements in the array
    for ($i = 0; $i <$n; $i++)
    {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare($a[$i]))
            $maxi = max($a[$i], $maxi);
    }
 
    return $maxi;
}
 
// Driver Code
$a = array( 16, 20, 25, 2, 3, 10 );
 
$n = count($a);
 
echo largestPerfectSquareNumber($a, $n);
 
// This code is contributed
// by inder_verma.
?>

Javascript

<script>
 
// Javascript program to find the largest perfect
// square number among n numbers
 
// Function to check if a number
// is perfect square number or not
function checkPerfectSquare(n)
{
    // takes the sqrt of the number
    let d = Math.sqrt(n);
 
    // checks if it is a perfect
    // square number
    if (d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest perfect
// square number in the array
function largestPerfectSquareNumber(a, n)
{
    // stores the maximum of all
    // perfect square numbers
    let maxi = -1;
 
    // Traverse all elements in the array
    for (let i = 0; i < n; i++)
    {
 
        // store the maximum if current
        // element is a perfect square
        if (checkPerfectSquare(a[i]))
            maxi = Math.max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
let a = [ 16, 20, 25, 2, 3, 10 ];
let n = a.length;
document.write(largestPerfectSquareNumber(a, n));
 
// This code is contributed by souravmahato348.
</script>
Producción: 

25

 

Complejidad temporal: O( N * \sqrt{A_i} )
Espacio auxiliar: O(1) 

Publicación traducida automáticamente

Artículo escrito por VishalBachchas y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA

Deja una respuesta

Tu dirección de correo electrónico no será publicada. Los campos obligatorios están marcados con *