Submission #395736

#	Time	Username	Problem	Language	Result	Execution time	Memory
395736		peuch	Red-blue table (IZhO19_stones)	C++17	100 / 100	129 ms	2244 KiB

stones

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

const int MAXN = 1010;

int t;
int n, m;
int k, l;
int ans;
int in[MAXN];
char grid[MAXN][MAXN];
bool inv;

set<pair<int, int> > s;

int main(){
	scanf("%d", &t);
	while(t--){
		s.clear();
		scanf("%d %d", &n, &m);
		if(n < m) swap(n, m), inv = true;
		else inv = false;
		k = n / 2 + 1;
		l = m / 2 + 1;
		ans = n;
		
		for(int i = 1; i <= n; i++){
			for(int j = 1; j <= m; j++)
				grid[i][j] = (inv) ? '-' : '+';
			s.insert(make_pair(-m, i));
			in[i] = m;
		}
		
		for(int j = 1; j <= m; j++){
			vector<int> ids;
			bool flag = false;
			for(int _ = 0; _ < k; _++){
				ids.push_back(s.begin()->second);
				if(s.begin()->first == -l) flag = true;
				s.erase(s.begin());
			}
			if(flag) break;
			ans++;
			
			for(int i = 0; i < ids.size(); i++){
				int cur = ids[i];
				in[cur]--;
				s.insert(make_pair(-in[cur], cur));
				grid[cur][j] = (inv) ? '+' : '-';
			}
		}
		
		printf("%d\n", ans);
		if(inv) swap(n, m);
		for(int i = 1; i <= n; i++){
			for(int j = 1; j <= m; j++){
				printf("%c", (inv) ? grid[j][i] : grid[i][j]);
			}
			printf("\n");
		}
	}
}

Compilation message (stderr)

stones.cpp: In function 'int main()':
stones.cpp:45:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |    for(int i = 0; i < ids.size(); i++){
      |                   ~~^~~~~~~~~~~~
stones.cpp:17:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d", &t);
      |  ~~~~~^~~~~~~~~~
stones.cpp:20:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |   scanf("%d %d", &n, &m);
      |   ~~~~~^~~~~~~~~~~~~~~~~

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