Submission #1870132

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Source Code Expand

#include <iostream>
#include <algorithm>

using namespace std;

int K, T;
int a[105];

int main(void)
{
	cin >> K >> T;
	for(int i = 0; i < T; i++) cin >> a[i];
	sort(a, a+T);
	reverse(a, a+T);
	
	if(T == 1){
		cout << a[0]-1 << endl;
		return 0;
	}
	if(T == 2){
		cout << max(0, a[0] - a[1] - 1) << endl;
		return 0;
	}
	
	int sum = 0;
	for(int i = 2; i < T; i++) sum += a[i];
	cout << max(0, a[0] - a[1] - sum - 1) << endl;
	return 0;
}

Submission Info

Judge Result