不是完美立方体的数组中的最大数字

给定一个由n个整数组成的数组。任务是找到最大的数字，而不是一个完美的立方体。如果没有数字是一个理想的立方体，则打印-1。
例子：

Input: arr[] = {16, 8, 25, 2, 3, 10} 
Output: 25
25 is the largest number that is not a perfect cube. 

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

一个简单的解决方案是使用cbrt()函数对元素进行排序，然后对数字进行排序，然后从后面开始检查是否有不完美的多维数据集数字。从结尾开始的第一个数字(不是完美的立方数)是我们的答案。排序的复杂度为O(n log n)，而cbrt()函数的复杂度为log n，因此在最坏的情况下，复杂度为O(n log n)。
一个有效的解决方案是对O(n)中的所有元素进行迭代，并每次与最大元素进行比较，并存储所有非完美立方体的最大值。
下面是上述方法的实现：

C++

// CPP program to find the largest non-perfect
// cube number among n numbers
 
#include 
using namespace std;
 
// Function to check if a number
// is perfect cube number or not
bool checkPerfectcube(int n)
{
    // takes the sqrt of the number
    int d = cbrt(n);
 
    // checks if it is a perfect
    // cube number
    if (d * d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest non perfect
// cube number in the array
int largestNonPerfectcubeNumber(int a[], int n)
{
    // stores the maximum of all
    // perfect cube 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 non perfect cube
        if (!checkPerfectcube(a[i]))
            maxi = max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
int main()
{
    int a[] = { 16, 64, 25, 2, 3, 10 };
 
    int n = sizeof(a) / sizeof(a[0]);
 
    cout << largestNonPerfectcubeNumber(a, n);
 
    return 0;
}

Java

// Java program to find the largest non-perfect
// cube number among n numbers
 
import java.io.*;
 
class GFG {
   
 
// Function to check if a number
// is perfect cube number or not
static boolean checkPerfectcube(int n)
{
    // takes the sqrt of the number
    int d = (int)Math.cbrt(n);
 
    // checks if it is a perfect
    // cube number
    if (d * d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest non perfect
// cube number in the array
static int largestNonPerfectcubeNumber(int []a, int n)
{
    // stores the maximum of all
    // perfect cube 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 non perfect cube
        if (!checkPerfectcube(a[i]))
            maxi = Math.max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
 
 
    public static void main (String[] args) {
    int a[] = { 16, 64, 25, 2, 3, 10 };
 
    int n = a.length;
 
    System.out.print( largestNonPerfectcubeNumber(a, n));
    }
}
// This code is contributed
// by inder_verma

Python 3

# Python 3 program to find the largest
# non-perfect cube number among n numbers
import math
 
# Function to check if a number
# is perfect cube number or not
def checkPerfectcube(n):
     
    # takes the sqrt of the number
    cube_root = n ** (1./3.)
    if round(cube_root) ** 3 == n:
        return True
    else:
        return False
 
# Function to find the largest non
# perfect cube number in the array
def largestNonPerfectcubeNumber(a, n):
     
    # stores the maximum of all
    # perfect cube numbers
    maxi = -1
 
    # Traverse all elements in the array
    for i in range(0, n, 1):
         
        # store the maximum if current
        # element is a non perfect cube
        if (checkPerfectcube(a[i]) == False):
            maxi = max(a[i], maxi)
     
    return maxi
 
# Driver Code
if __name__ == '__main__':
    a = [16, 64, 25, 2, 3, 10]
 
    n = len(a)
 
    print(largestNonPerfectcubeNumber(a, n))
 
# This code is contributed by
# Surendra_Gangwar

C#

// C# program to find the largest non-perfect
// cube number among n numbers
using System;
public class GFG {
 
 
    // Function to check if a number
    // is perfect cube number or not
    static bool checkPerfectcube(int n)
    {
        // takes the sqrt of the number
        int d = (int)Math.Ceiling(Math.Pow(n, (double)1 / 3));
 
        // checks if it is a perfect
        // cube number
        if (d * d * d == n)
            return true;
 
        return false;
    }
 
    // Function to find the largest non perfect
    // cube number in the array
    static int largestNonPerfectcubeNumber(int []a, int n)
    {
        // stores the maximum of all
        // perfect cube 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 non perfect cube
            if (checkPerfectcube(a[i])==false)
                maxi = Math.Max(a[i], maxi);
        }
 
        return maxi;
    }
 
    // Driver Code
 
 
        public static void Main () {
        int []a = { 16, 64, 25, 2, 3, 10 };
 
        int n = a.Length;
 
        Console.WriteLine( largestNonPerfectcubeNumber(a, n));
        }
}
/*This code is contributed by PrinciRaj1992*/

Javascript

// Javascript program to find the largest non-perfect
// cube number among n numbers
 
// Function to check if a number
// is perfect cube number or not
function checkPerfectcube(n)
{
 
    // takes the sqrt of the number
    let d = Math.cbrt(n);
 
    // checks if it is a perfect
    // cube number
    if (d * d * d == n)
        return true;
 
    return false;
}
 
// Function to find the largest non perfect
// cube number in the array
function largestNonPerfectcubeNumber(a, n)
{
    // stores the maximum of all
    // perfect cube 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 non perfect cube
        if (!checkPerfectcube(a[i]))
            maxi = Math.max(a[i], maxi);
    }
 
    return maxi;
}
 
// Driver Code
let a = [ 16, 64, 25, 2, 3, 10 ];
let n = a.length;
document.write(largestNonPerfectcubeNumber(a, n));
 
// This code is contributed by souravmahato348.

输出：

25

时间复杂度： O(n)

辅助空间： O(1)