Submission #1164167

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Source Code Expand

#include<cstdio>
#include <iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>

using namespace std;
typedef long long ll;
typedef pair<int, int>P;


int main() {
	int K, T;
	cin >> K >> T;

	int a[110];
	for (int i = 0; i < T; i++)
		cin >> a[i];

	sort(a, a + T);
	reverse(a,a + T);

	cout << max(a[0] - 1-(K - a[0]), 0) << endl;
	return 0;
}

Submission Info

Judge Result