查找隐藏号码的程序

给定一个数组$n$整数，任务是找到另一个整数$x$这样，如果从数字中分别减去数组的所有元素$x$ ，则所有差异的总和应加到0。如果存在任何这样的整数，则打印的值$x$ ，否则打印$-1$ 。

例子

Input: arr[] = {1, 2, 3}
Output: 2
Explanation: 
Substracting all the elements of arrays from 2,
The sum of difference is:
1 + 0 + (-1) = 0.

解决方案：想法是计算数组的总和，然后将其除以数组的大小。如果数组的总和可以完全按其大小整除，则从该除法运算获得的商将是所需的隐藏数。

下面是上述想法的实现：

C++

// C++ Program to find the
// hidden number
  
#include 
using namespace std;
  
    // Driver Code
  
int main() {
        // Getting the size of array
        int n = 3;
  
        // Getting the array of size n
        int a[] = { 1, 2, 3 };
  
        // Solution
        int i = 0;
  
        // Finding sum of the array elements
        long sum = 0;
        for (i = 0; i < n; i++) {
            sum += a[i];
        }
  
        // Dividing sum by size n
        long x = sum / n;
  
        // Print x, if found
        if (x * n == sum)
            cout<

---

Java

// Java Program to find the
// hidden number
  
public class GFG {
  
    // Driver Code
    public static void main(String args[])
    {
  
        // Getting the size of array
        int n = 3;
  
        // Getting the array of size n
        int a[] = { 1, 2, 3 };
  
        // Solution
        int i = 0;
  
        // Finding sum of the array elements
        long sum = 0;
        for (i = 0; i < n; i++) {
            sum += a[i];
        }
  
        // Dividing sum by size n
        long x = sum / n;
  
        // Print x, if found
        if (x * n == sum)
            System.out.println(x);
        else
            System.out.println("-1");
    }
}

Python 3

# Python 3 Program to find the
# hidden number
  
# Driver Code
if __name__ == "__main__":
      
    # Getting the size of array
    n = 3
  
    # Getting the array of size n
    a = [ 1, 2, 3 ]
  
    # Solution
    i = 0
  
    # Finding sum of the .
    # array elements
    sum = 0
    for i in range(n):
        sum += a[i]
  
    # Dividing sum by size n
    x = sum // n
  
    # Print x, if found
    if (x * n == sum):
        print(x)
    else:
        print("-1")
  
# This code is contributed 
# by ChitraNayal

C#

// C# Program to find the
// hidden number
using System; 
  
class GFG
{ 
  
// Driver Code 
public static void Main() 
{ 
  
    // Getting the size of array 
    int n = 3; 
  
    // Getting the array of size n 
    int []a = { 1, 2, 3 }; 
  
    // Solution 
    int i = 0; 
  
    // Finding sum of the
    // array elements 
    long sum = 0; 
    for (i = 0; i < n; i++) 
    { 
        sum += a[i]; 
    } 
  
    // Dividing sum by size n 
    long x = sum / n; 
  
    // Print x, if found 
    if (x * n == sum) 
        Console.WriteLine(x); 
    else
        Console.WriteLine("-1"); 
} 
} 
  
// This code is contributed
// by inder_verma

输出：

2