import std;

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

    int acc = 0;
    foreach (a; A) {
        acc += a;
    }

    int ans = max(acc - X, 0);
    writeln(ans);
}

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