Submission #1986599

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
typedef int64_t ll;
typedef vector<ll> vll;
struct Solution {
    void solve(std::istream& in, std::ostream& out) {
        ll k, t;
        in >> k >> t;
        vll a(t);
        ll ma = 0;
        for (int i = 0; i < t; i++) {
            in >> a[i];
            ma = max(ma, a[i]);
        }
        out << max(0LL, ma - (k - ma) - 1LL) << '\n';
    }
};
void solve(std::istream& in, std::ostream& out) {
    out << std::setprecision(12);
    Solution solution;
    solution.solve(in, out);
}
#include <fstream>
#include <iostream>
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    istream& in = cin;
    ostream& out = cout;
    solve(in, out);
    return 0;
}

Submission Info

Judge Result