Submission #788773

#	Time	Username	Problem	Language	Result	Execution time	Memory
788773		TheOpChicken	Red-blue table (IZhO19_stones)	C++17	27 / 100	45 ms	1256 KiB

stones

#include <bits/stdc++.h>
using namespace std;

bool possible(int i, int n, int m, int mid){
	int total = (n-i)*mid + i*min(mid, m-(m/2+1));
	return total >= mid*(n/2+1);
}

int find_can(int i, int n, int m){
	int l = 0, r = m, ans = 0;
	while(l <= r){
		int mid = (l+r)/2;
		if (!possible(i, n, m, mid)) r = mid-1;
		else{
			ans = mid;
			l = mid+1;
		}
	}

	return ans;
}

int main(){
	int t;
	cin >> t;
	while(t--){
		int n, m;
		cin >> n >> m;

		int opt = 0, can = -1;
		for (int i = 0; i <= n; i++){
			int new_can = find_can(i, n, m);
			if (new_can+i > opt+can) opt = i, can = new_can;
		}

		vector<int> count(m, 0);
		vector<vector<char> > grid(n, vector<char>(m));

		cout << can + opt << endl;
		for (int i = 0; i < n; i++){
			int row_need = m/2 + 1;
			for (int j = 0; j < m; j++){
				if (i < n-opt) grid[i][j] = '-', count[j]++;
				else{
					if (row_need == m - j || j >= can || count[j] == n/2+1){
						grid[i][j] = '+';
						row_need--;
					}
					else{
						grid[i][j] = '-';
						count[j]++;
					}
				}
			}
		}

		for (int i = 0; i < n; i++){
			for (int j = 0; j < m; j++) cout << grid[i][j];
			cout << endl;
		}
	}
}

• Subtask 1: 17 / 17
• Subtask 2: 10 / 10
• Subtask 3: 0 / 16
• Subtask 4: 0 / 11
• Subtask 5: 0 / 15
• Subtask 6: 0 / 31