import std;

void main () {
    int N, X; readln.read(N, X);
    int[] A = readln.split.to!(int[]);

    // 累積 + 二分探索(2周)
    long[] cum = new long[](2*N+1);
    cum[0] = 0;
    for (int i = 1; i <= 2*N; i++) cum[i] = cum[i-1] + A[(i-1)%N];

    bool f (int i, int x) {
        x++; // 1-indexed
        return cum[x] - cum[i] <= X;
    }

    long ans = 0;
    foreach (i; 0..N) {
        int ok = i, ng = i+N;
        while (1 < abs(ok-ng)) {
            int mid = (ok+ng) / 2;
            if (f(i, mid)) {
                ok = mid;
            }
            else {
                ng = mid;
            }
        }

        if (cum[ok+1]-cum[i] <= X) ans = max(ans, cum[ok+1]-cum[i]);
    }

    writeln(ans);
}

void read (T...) (string S, ref T args) {
    auto buf = S.split;
    foreach (i, ref arg; args) {
        arg = buf[i].to!(typeof(arg));
    }
}