Submission #370942

#	Time	Username	Problem	Language	Result	Execution time	Memory
370942		fhvirus	Red-blue table (IZhO19_stones)	C++17	100 / 100	42 ms	2284 KiB

stones

// Knapsack DP is harder than FFT.
#include<bits/stdc++.h>
using namespace std;
typedef int64_t ll;
typedef pair<int,int> pii; typedef pair<ll,ll> pll;
#define ff first
#define ss second
#define pb emplace_back
#define FOR(i,n) for(int i=0;i<(n);++i)
#define FOO(i,a,b) for(int i=(a);i<=int(b);++i)
#define OOF(i,a,b) for(int i=(a);i>=int(b);--i)
#define AI(x) (x).begin(),(x).end()
template<class I>bool chmax(I&a,I b){return a<b?(a=b,true):false;}
template<class I>bool chmin(I&a,I b){return b<a?(a=b,true):false;} 
template<class V>void lisan(V&v){sort(AI(v));v.erase(unique(AI(v)),v.end());}
template<class V,class T>int lspos(const V&v,T x){return lower_bound(AI(v),x)-v.begin();}
template<class...T>void RI(T&...t){(...,(cin>>t));}
template<class...T>void PL(T...t){int c=sizeof...(T);if(!c){cout<<'\n';return;}(...,(cout<<t<<(--c?' ':'\n')));}
constexpr inline ll cdiv(ll x,ll m){return x/m+(x%m?(x<0)^(m>0):0);}
constexpr inline ll mpow(ll x,ll e,ll m){ll r=1;for(x%=m;e;e/=2,x=x*x%m)if(e&1)r=r*x%m;return r;}
#ifdef OWO
#define safe cerr<<"\033[1;32m"<<__PRETTY_FUNCTION__<<" - "<<__LINE__<<" JIZZ\033[0m\n"
#define debug(args...) SDF(#args, args)
#define OIU(args...) ostream& operator<<(ostream&O,args)
#define LKJ(S,B,E,F) template<class...T>OIU(S<T...>s){O<<B;int c=0;for(auto i:s)O<<(c++?", ":"")<<F;return O<<E;}
LKJ(vector,'[',']',i)LKJ(deque,'[',']',i)LKJ(set,'{','}',i)LKJ(multiset,'{','}',i)LKJ(unordered_set,'{','}',i)LKJ(map,'{','}',i.ff<<':'<<i.ss)LKJ(unordered_map,'{','}',i.ff<<':'<<i.ss)
template<class...T>OIU(pair<T...>p){return O<<'('<<p.ff<<','<<p.ss<<')';}
template<class T,size_t N>OIU(array<T,N>a){return O<<vector<T>(AI(a));}
template<class...T>OIU(tuple<T...>t){return O<<'(',apply([&O](T...s){int c=0;(...,(O<<(c++?", ":"")<<s));},t),O<<')';}
template<class...T>void SDF(const char* s,T...a){int c=sizeof...(T);if(!c){cerr<<"\033[1;32mvoid\033[0m\n";return;}(cerr<<"\033[1;32m("<<s<<") = (",...,(cerr<<a<<(--c?", ":")\033[0m\n")));}
#else
#pragma GCC optimize("Ofast")
#define safe ((void)0)
#define debug(...) ((void)0)
#endif
constexpr ll inf = 1e9, INF = 4e18;
const int N = 1001;
char a[N][N];
int t, n, m;
int cnt[N];
void solve(){
	cin >> n >> m;

	bool rot = false;
	if(n > m) rot = true, swap(n, m);
	FOR(i,n) FOR(j,m) a[i][j] = '-';

	FOR(j,m) cnt[j] = n;
	int k = 0;
	FOR(i,n){
		FOR(j,m/2+1){
			if(cnt[k] - 1 > n - (cnt[k] - 1)) a[i][k] = '+', --cnt[k];
			++k;
			if(k >= m) k = 0;
		}
	}
	if(rot){
		FOR(i,m) FOR(j,i) swap(a[i][j], a[j][i]);
		FOR(i,m) FOR(j,n) a[i][j] ^= ('+' ^ '-');
		swap(n, m);
	}

	int ans = 0;
	FOR(i,n){
		int sum = 0;
		FOR(j,m) sum += (a[i][j] == '+');
		ans += (sum > m - sum);
	}
	FOR(j,m){
		int sum = 0;
		FOR(i,n) sum += (a[i][j] == '-');
		ans += (sum > n - sum);
	}
	cout << ans << '\n';
	FOR(i,n){
		FOR(j,m) cout << a[i][j];
		cout << '\n';
	}
}
int32_t main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin >> t;
	for(; t; --t) solve();
	return 0;
}

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