Minimum Value Among Elements of Every Subset of an Array in C++

Problem statement

Given an array of integers, the task is to find the AND of all elements of each subset of the array and print the minimum AND value among all those.

Example

If arr[] = {1, 2, 3, 4, 5} then
(1 & 2) = 0
(1 & 3) = 1
(1 & 4) = 0
(1 & 5) = 1
(2 & 3) = 2
(2 & 4) = 0
(2 & 5) = 0
(3 & 4) = 0
(3 & 5) = 1
(4 & 5) = 4

Algorithm

• The minimum AND value of any subset of the array will be the AND of all the elements of the array.
• So, the simplest way is to find AND of all elements of subarray.

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
int getMinAndValue(int *arr, int n) {
   int result = arr[0];
   for (int i = 1; i < n; ++i) {
      result = result & arr[i];
   }
   return result;
}
int main() {
   int arr[] = {1, 2, 3, 4, 5};
   int n = sizeof(arr) / sizeof(arr[0]);
   cout << "Minimum value = " << getMinAndValue(arr, n) << endl;
   return 0;
}

When you compile and execute above program. It generates following output −

Output

Minimum value = 0