CF1490G AC

#include <assert.h>
#include <bits/stdc++.h>
using namespace std;
#define dbg(...) logger(#__VA_ARGS__, __VA_ARGS__)
template <typename... Args> void logger(string vars, Args &&... values)
{
    cerr << vars << " = ";
    string delim = "";
    (..., (cerr << delim << values, delim = ", "));
    cerr << endl;
}

template <class T> inline auto vv(int m) { return vector<vector<T>>(m, vector<T>(m)); }
template <class T> inline auto vv(int m, int n) { return vector<vector<T>>(m, vector<T>(n)); }
template <class T, T init> inline auto vv(int m) { return vector<vector<T>>(m, vector<T>(m, init)); }
template <class T, T init> inline auto vv(int m, int n) { return vector<vector<T>>(m, vector<T>(n, init)); }

template <class T> using mpq = priority_queue<T, vector<T>, greater<T>>;

using ll = long long;
using pii = pair<int, int>;
using vl = vector<ll>;
using vi = vector<int>;

int main(int argc, char **argv)
{
    int t;
    cin >> t;
    while (t--) {
        int n, m;
        cin >> n >> m;
        vector<ll> a(n);
        ll acc = 0;
        vector<ll> pref;
        map<ll, int> cmap;

        for (int i = 0; i < n; ++i) {
            cin >> a[i];
            acc += a[i];
            if (acc > 0 && (pref.size() == 0 || acc > pref.back())) {
                pref.push_back(acc);
                cmap[acc] = i;
            }
        }
        // dbg(acc);

        ll x;
        for (int i = 0; i < m; ++i) {
            cin >> x;
            int lb = lower_bound(pref.begin(), pref.end(), x) - pref.begin();
            if (lb != pref.size()) {
                // dbg(x, lb, "case 1");
                cout << cmap[pref[lb]] << ' ';
            } else if (acc > 0) {
                ll repeat = (x - pref.back() + acc - 1) / acc;
                ll delta = x - repeat * acc;
                ll lb = lower_bound(pref.begin(), pref.end(), delta) - pref.begin();
                ll ans = repeat * n + cmap[pref[lb]];
                // dbg(repeat, n, delta, lb, ans);
                cout << ans << ' ';
            } else {
                // dbg(x, lb, "case 3");
                cout << -1 << ' ';
            }
        }
        cout << '\n';
    }
    return 0;
};