Submission #930892

#	Time	Username	Problem	Language	Result	Execution time	Memory
930892		phoenix0423	Furniture (JOI20_furniture)	C++17	100 / 100	198 ms	51504 KiB

furniture

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define int long long
typedef pair<int, int> pll;
#define fastio ios::sync_with_stdio(false), cin.tie(0)
#define pb push_back
#define eb emplace_back
#define f first
#define s second
#define lowbit(x) x&-x;
const int maxn = 1005;
const int maxq = 1e6 + 5;
const int INF = 1e18;
int c[maxn][maxn];
int st[maxn][maxn];
pll coord[maxq];
int cnt[maxn * 2];
int ans[maxq];
int n, m, q;
int dx[] = {0, 1, 0, -1};
int dy[] = {1, 0, -1, 0};
bool inbound(int x, int y){ return x >= 0 && y >= 0 && x < n && y < m;}

void remove(int x, int y){
    if(!st[x][y]) return;
    st[x][y] = 0, cnt[x + y] --;
    queue<pll> q;
    q.push({x, y});
    while(!q.empty()){
        auto [cx, cy] = q.front(); q.pop();
        for(int d = 2; d < 4; d++){
            int xx = cx + dx[d], yy = cy + dy[d];
            if(!inbound(xx, yy) || !st[xx][yy]) continue;
            if(!st[xx + 1][yy] && !st[xx][yy + 1]){
                cnt[xx + yy] --;
                st[xx][yy] = 0;
                q.push({xx, yy});
            }
        }
    }
    q.push({x, y});
    while(!q.empty()){
        auto [cx, cy] = q.front(); q.pop();
        for(int d = 0; d < 2; d++){
            int xx = cx + dx[d], yy = cy + dy[d];
            if(!inbound(xx, yy) || !st[xx][yy]) continue;
            int bad = (xx == 0 || !st[xx - 1][yy]) + (yy == 0 || !st[xx][yy - 1]);
            if(bad == 2){
                cnt[xx + yy] --;
                st[xx][yy] = 0;
                q.push({xx, yy});
            }
        }
    }
}

signed main(void){
    fastio;
    cin>>n>>m;
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++) cin>>c[i][j];
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++) st[i][j] = 1, cnt[i + j] ++;
    }
    cin>>q;
    for(int i = 0; i < q; i++){
        cin>>coord[i].f>>coord[i].s;
        coord[i].f--, coord[i].s--;
    }
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++){
            if(c[i][j]){
                remove(i, j);
            }
        }
    }
    for(int i = 0; i < q; i++){
        auto [x, y] = coord[i];
        if(st[x][y] && cnt[x + y] == 1) continue;
        if(st[x][y]) remove(x, y);
        ans[i] = 1;
    }
    for(int i = 0; i < q; i++) cout<<ans[i]<<"\n";
}

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