Oro (13/20, TLE)

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

int p, m, n, finalpos = -1;
vector<int> g;

void f(int pos, int i) {
    if (i == n) {
        finalpos = max(pos, finalpos);
        return;
    }
    int x = g[i];
    if (pos-x >= 0) {
        f(pos-x, i+1);
    }
    if (pos+x <= m) {
        f(pos+x, i+1);
    }
}

int main() {
//    std::ios::sync_with_stdio(false);
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);

    cin >> p >> m >> n;
    g.resize(n);
    for (int i = 0; i < n; ++i) cin >> g[i];

    f(p, 0);
    cout << finalpos << endl;
}