#include <bits/stdc++.h>
#define ll long long
#define zero  cout << 0 << '\n' ;
#define opps cout<<-1<<'\n';
const int MAX = 1e7;
using namespace std;
void solve() {
    int n , w ;
    cin>>n>>w;
    vector<ll> a(n);
    for(int i=0;i<n;i++)
        cin>>a[i];
    ll l = 0 , r = 0 , ans = 0, sumx =0;
    while (r < n) {
        sumx += a[r];
        while (sumx > w && l <= r)
            sumx -=a[l++];
        r++;
        ans = max(ans , sumx);
    }
    cout<<ans<<'\n' ;
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int t=1;
    cin>>t;
    while (t--)
        solve();
    return 0;
}