Using_Recursion

#include<bits/stdc++.h>
using namespace std;
int recursivesum(int currind, int end, int a[])
{
    if (currind == end) return 0;
    int sum = a[currind] + recursivesum(currind + 1, end, a);
    return sum;
}

int recursivemax(int currind, int end, int a[])
{
    if (currind == end) return -INT_MAX;
    int mx = max(a[currind], recursivemax(currind + 1, end, a));
    return mx;
}


int recursivemin(int currind, int end, int a[])
{
    if (currind == end) return INT_MAX;
    int mn = min(a[currind], recursivemin(currind + 1, end, a));
    return mn;
}



void findsum(vector<int>& a, int l, int r, int &sum, int &count, int& ans, int x)
{

    if (sum == x)
    {
        ans = min(ans, count);
        return ;
    }

    ////base case
    if (l > r) return;

    ///////taking the left most element
    sum += a[l]; count++;
    findsum(a, l + 1, r, sum, count, ans, x);

    //backtracking step
    sum -= a[l]; count--;

    ///////taking the righmost element
    sum += a[r]; count++;
    findsum(a, l, r - 1, sum, count, ans, x);

    sum -= a[r]; count--;
    return;
}

int main()
{
    int n, x; cin >> n >> x;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++) cin >> a[i];


    // int sum = recursivesum(1, n + 1, a);
    // cout << "Sum-> " << sum << endl;


    // int mx = recursivemax(1, n + 1, a);
    // cout << "Max-> " << mx << endl;


    // int mn = recursivemin(1, n + 1, a);
    // cout << "Min-> " << mn << endl;

    int sum = 0, count = 0, ans = INT_MAX;
    findsum(a, 1, n, sum, count, ans, x);

    if (ans == INT_MAX)
    {
        ///answer is not updated
        cout << "-1" << endl;
    }
    else cout << ans << endl;

    return 0;
}