为数组的每个元素找到最近的完美正方形

原文:https://www . geeksforgeeks . org/查找数组中每个元素的最近完美平方/

给定一个由 N 正整数组成的数组 arr[] ,任务是为每个数组元素打印最近的完美正方形

示例:

输入: arr[] = {5,2,7,13} 输出: 4 1 9 16 解释: arr0最近的完美平方是 4。 arr1的最近完美平方是 1。 arr2的最近完美平方是 9。 arr3的最近完美平方是 16。

输入: arr[] = {31,18,64} 输出: 36 16 64

方法:按照以下步骤解决问题:

  • 从左到右遍历数组
  • 对于每个数组元素,找到最近的完美正方形
    • 如果 N完美正方形那么打印 N
    • 否则,找到第一个 完美方块 编号 > N 并注意其与 N 的区别。
    • 然后,找到第一个完美平方数 < N ,并注意其与 N 的区别。
    • 并打印完美的正方形,得到这两个差值的最小

下面是上述方法的实现:

C++

// C++ program for the above approach

#include <bits/stdc++.h>
using namespace std;

// Function to find the nearest perfect square
// for every element in the given array
void nearestPerfectSquare(int arr[], int N)
{

    // Traverse the array
    for (int i = 0; i < N; i++) {

        // Calculate square root of
        // current  element
        int sr = sqrt(arr[i]);

        // Calculate perfect square
        int a = sr * sr;
        int b = (sr + 1) * (sr + 1);

        // Find the nearest
        if ((arr[i] - a) < (b - arr[i]))
            cout << a << " ";
        else
            cout << b << " ";
    }
}

// Driver Code
int main()
{
    int arr[] = { 5, 2, 7, 13 };
    int N = sizeof(arr) / sizeof(arr[0]);
    nearestPerfectSquare(arr, N);
    return 0;
}

Java 语言(一种计算机语言,尤用于创建网站)

// Java program for the above approach
import java.io.*;

class GFG{

// Function to find the nearest perfect square
// for every element in the given array
static void nearestPerfectSquare(int[] arr, int N)
{

    // Traverse the array
    for(int i = 0; i < N; i++)
    {

        // Calculate square root of
        // current  element
        int sr = (int)Math.sqrt(arr[i]);

        // Calculate perfect square
        int a = sr * sr;
        int b = (sr + 1) * (sr + 1);

        // Find the nearest
        if ((arr[i] - a) < (b - arr[i]))
            System.out.print(a + " ");
        else
            System.out.print(b + " ");
    }
}

// Driver Code
public static void main(String[] args)
{
    int[] arr = { 5, 2, 7, 13 };
    int N = arr.length;

    nearestPerfectSquare(arr, N);
}
}

// This code is contributed by souravmahato348

Python 3

# Python program for the above approach
# Function to find the nearest perfect square
# for every element in the given array
# import the math module
import math
def nearestPerfectSquare(arr,N):

    # Traverse the array
    for i in range(0,N):

        # Calculate square root of
        # current  element
        sr = math.floor(math.sqrt(arr[i]))

        # Calculate perfect square
        a = sr * sr
        b = (sr + 1) * (sr + 1)

        # Find the nearest
        if ((arr[i] - a) < (b - arr[i])):
           print(a ,end=" ")
        else :
           print(b ,end=" ")

# Driver Code
arr =  [5, 2, 7, 13]
N = len(arr)
nearestPerfectSquare(arr, N)

# This code is contributed by shivanisinghss2110

C#

// C# program for the above approach
using System;
class GFG
{

    // Function to find the nearest perfect square
    // for every element in the given array
    static void nearestPerfectSquare(int[] arr, int N)
    {

        // Traverse the array
        for (int i = 0; i < N; i++) {

            // Calculate square root of
            // current  element
            int sr = (int)Math.Sqrt(arr[i]);

            // Calculate perfect square
            int a = sr * sr;
            int b = (sr + 1) * (sr + 1);

            // Find the nearest
            if ((arr[i] - a) < (b - arr[i]))
                Console.Write(a + " ");
            else
                Console.Write(b + " ");
        }
    }

    // Driver Code
    public static void Main()
    {
        int[] arr = { 5, 2, 7, 13 };
        int N = arr.Length;

        nearestPerfectSquare(arr, N);
    }
}

// This code is contributed by souravmahato348

java 描述语言

<script>

// JavaScript program for the above approach

// Function to find the nearest perfect square
// for every element in the given array
function nearestPerfectSquare(arr, N)
{

    // Traverse the array
    for (let i = 0; i < N; i++) {

        // Calculate square root of
        // current  element
        let sr = parseInt(Math.sqrt(arr[i]));

        // Calculate perfect square
        let a = sr * sr;
        let b = (sr + 1) * (sr + 1);

        // Find the nearest
        if ((arr[i] - a) < (b - arr[i]))
            document.write(a + " ");
        else
            document.write(b + " ");
    }
}

// Driver Code
    let arr = [ 5, 2, 7, 13 ];
    let N = arr.length;
    nearestPerfectSquare(arr, N);

</script>

**Output: 

4 1 9 16**

*时间复杂度:O(N * sqrt(arr[I])***

*辅助空间: O(1)***