Submission #342276

#	Time	Username	Problem	Language	Result	Execution time	Memory
342276		ryansee	Furniture (JOI20_furniture)	C++14	0 / 100	6 ms	8428 KiB

furniture

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

#define FAST ios_base::sync_with_stdio(false); cin.tie(0);
#define pb push_back
#define eb emplace_back
#define ins insert
#define f first
#define s second
#define cbr cerr<<"hi\n"
#define mmst(x, v) memset((x), v, sizeof ((x)))
#define siz(x) ll(x.size())
#define all(x) (x).begin(), (x).end()
#define lbd(x,y) (lower_bound(all(x),y)-x.begin())
#define ubd(x,y) (upper_bound(all(x),y)-x.begin())
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());    //can be used by calling rng() or shuffle(A, A+n, rng)
inline long long rand(long long x, long long y) { return rng() % (y+1-x) + x; } //inclusivesss
string inline to_string(char c) {string s(1,c);return s;} template<typename T> inline T gcd(T a,T b){ return a==0?llabs(b):gcd(b%a,a); }

using ll=long long; 
using ld=long double;
#define FOR(i,s,e) for(ll i=s;i<=ll(e);++i)
#define DEC(i,s,e) for(ll i=s;i>=ll(e);--i)
using pi=pair<ll,ll>; using spi=pair<ll,pi>; using dpi=pair<pi,pi>; 

long long LLINF = 1e18;
int INF = 1e9+1e6;
#define MAXN (1006)
ll n,m,q,cnt[MAXN*2],R[MAXN][MAXN];
bool A[MAXN][MAXN];
bool dp(ll x,ll y) {
	if(x > n || y > m || A[x][y]) return 0;
	if(~R[x][y]) return R[x][y];
	return R[x][y] = dp(x+1, y) | dp(x, y+1);
}
void gg(ll x,ll y) {
	if(R[x][y]==0) return;
	-- cnt[x+y], R[x][y] = 0;
}
bool chk(ll x,ll y) {
	return x >= 1 && y >= 1 && x <= n && y <= m && R[x][y];
}
void bck(ll x,ll y) {
	if(x < 1 || y < 1 || R[x][y] == 0) return;
	if(chk(x+1, y) || chk(x, y+1)) return;
	gg(x, y);
	bck(x-1, y), bck(x, y-1);
}
void bck2(ll x,ll y) {
	if(x > n || y > m || R[x][y] == 0) return;
	if(chk(x-1, y) || chk(x, y-1)) return;
	gg(x, y);
	bck2(x+1, y), bck(x, y+1);
}
int main() {
	mmst(R,-1);
	FAST
	cin>>n>>m;
	FOR(i,1,n)FOR(j,1,m)cin>>A[i][j];
	R[n][m]=1;
	dp(1, 1);
	FOR(i,1,n)FOR(j,1,m)if(R[i][j]==-1)R[i][j]=0;else if(R[i][j])++cnt[i+j];
	cin>>q;
	while(q--){
		ll x, y;
		cin>>x>>y;
		if(R[x][y] == 1 && cnt[x+y]==1) {
			cout<<0<<'\n';
			continue;
		}
		cout<<1<<'\n';
		gg(x, y);
		bck(x-1, y), bck(x, y-1);
		bck2(x+1, y), bck2(x, y+1);
	}
}

Compilation message (stderr)

furniture.cpp: In function 'bool dp(ll, ll)':
furniture.cpp:34:17: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   34 |  return R[x][y] = dp(x+1, y) | dp(x, y+1);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 95