Print distinct absolute differences of all possible pairs from a given array

// C++ implementation to find all
// Pairs possible from the given Array
#include <bits/stdc++.h>
using namespace std;

// Function to print all possible
// pairs from the array
void printPairs(int arr[], int n)
{
    unordered_set<int> s;

    // Nested loop for all possible pairs
    for (int i = 0; i < n; i++) {
        for (int j = i+1; j < n; j++) {
            s.insert(abs(arr[i] - arr[j]));
        }
    }
    
    for (auto x : s)
      cout << x << " ";
}

// Driver code
int main()
{
    int arr[] = { 1, 3, 6 };
    int n = sizeof(arr) / sizeof(arr[0]);

    printPairs(arr, n);

    return 0;
}

// C++ program for the above approach

#include <bits/stdc++.h>
using namespace std;
#define Max 100005

// Function to find all distinct
// absolute difference of all
// possible pairs of the array
void printUniqDif(int n, int a[])
{

    // bset[i]: Check if i is present
    // in the array or not
    bitset<Max> bset;

    // diff[i]: Check if there exists a
    // pair whose absolute difference is i
    bitset<Max> diff;

    // Traverse the array, arr[]
    for (int i = 0; i < n; i++) {

        // Add in bitset
        bset.set(a[i]);
    }

    // Iterate over the range[0, Max]
    for (int i = 0; i <= Max; i++) {

        // If i-th bit is set
        if (bset[i]) {

            // Insert the absolute difference
            // of all possible pairs whose
            // first element is arr[i]
            diff = diff | (bset >> i);
        }
    }

    // Stores count of set bits
    int X = bset.count();

    // If there is at least one
    // duplicate element in arr[]
    if (X != n) {

        cout << 0 << " ";
    }

    // Printing the distinct absolute
    // differences of all possible pairs
    for (int i = 1; i <= Max; i++) {

        // If i-th bit is set
        if (diff[i]) {
            cout << i << " ";
        }
    }
}

// Driver Code
int main()
{

    // Given array
    int a[] = { 1, 4, 6 };

    // Given size
    int n = sizeof(a) / sizeof(a[0]);

    // Function Call
    printUniqDif(n, a);

    return 0;
}