Submission #1017731

#	Time	Username	Problem	Language	Result	Execution time	Memory
1017731		Gray	Red-blue table (IZhO19_stones)	C++17	100 / 100	52 ms	5308 KiB

stones

#include <cassert>
#include <iostream>
#include <set>
#include <vector>
#define ll int
#define ln "\n"
#define ff first
#define ss second
#define ld long double
const ll INF = 1e9;
const ll MOD = 1e9+7;
using namespace std;

void solve(){
	ll n, m; cin >> n >> m;
	ll nform = n/2+1, mforn=m/2+1;
	cout << max((n-nform)*m/mforn+m,(m-mforn)*n/nform+n) << ln;
	if ((n-nform)*m/mforn+m>(m-mforn)*n/nform+n){
		vector<vector<ll>> ans(n, vector<ll>(m));
		multiset<pair<ll, ll>> vac; 
		for (ll i=0; i<(n-nform)*m/mforn; i++){
			vac.insert({0, i});
		}
		for (ll j=0; j<m; j++){
			for (ll i=0; i<n-nform; ++i){
				auto cur = *vac.begin();
				vac.erase(vac.begin());
				assert(ans[cur.ss][j]==0);
				ans[cur.ss][j]=2;
				vac.insert({cur.ff+1, cur.ss});
			}
		}
		for (ll i=0; i<n; i++){
			for (ll j=0; j<m; j++){
				cout << (ans[i][j]==2?"+":"-");
			}
			cout << ln;
		}
	}else{
		vector<vector<ll>> ans(n, vector<ll>(m));
		multiset<pair<ll, ll>> vac; 
		for (ll i=0; i<(m-mforn)*n/nform; i++){
			vac.insert({0, i});
		}
		for (ll i=0; i<n; i++){
			for (ll j=0; j<m-mforn; ++j){
				auto cur = *vac.begin();
				vac.erase(vac.begin());
				assert(ans[i][cur.ss]==0);
				ans[i][cur.ss]=2;
				vac.insert({cur.ff+1, cur.ss});
			}
		}
		for (ll i=0; i<n; i++){
			for (ll j=0; j<m; j++){
				cout << (ans[i][j]==2?"-":"+");
			}
			cout << ln;
		}
	}
}
void setIO(){
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
}
int main(){
	setIO();
	ll t=1;
	cin >> t;
	while (t--) solve();
}

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