Submission #358532

#	Time	Username	Problem	Language	Result	Execution time	Memory
358532		BartolM	Furniture (JOI20_furniture)	C++17	100 / 100	547 ms	19888 KiB

furniture

#include <bits/stdc++.h>

using namespace std;

#define X first
#define Y second
#define mp make_pair
#define pb push_back
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <int, pii> pip;
typedef pair <pii, int> ppi;
typedef pair <ll, ll> pll;

const int INF=0x3f3f3f3f;
const int N=1005;

int n, m, q;
int mat[N][N];
int dp[N][N], cnt[2*N];
int dx[4]={-1, 0, 1, 0};
int dy[4]={0, 1, 0, -1};
queue <pii> Q;

int ok(int x, int y) {
    if (x<=0 || y<=0 || x>n || y>m) return 0;
    if (!dp[x][y]) return 0;
    return (!dp[x-1][y] && !dp[x][y-1]) || (!dp[x+1][y] && !dp[x][y+1]);
}

void bfs(int x, int y) {
    Q.push(mp(x, y));
    while (!Q.empty()) {
        pii pp=Q.front();
        Q.pop();
        for (int i=0; i<4; ++i) {
            int nx=pp.X+dx[i], ny=pp.Y+dy[i];
            if (!ok(nx, ny)) continue;
            Q.push(mp(nx, ny));
            dp[nx][ny]=0;
            cnt[nx+ny]--;
        }
    }
}

void ispis() {
    printf("-----------------------\n");
    for (int i=1; i<=n; ++i) {
        for (int j=1; j<=m; ++j) {
            printf("%d ", dp[i][j]);
        }
        printf("\n");
    }
    printf("----------------------------\n");
}

void solve() {
    dp[0][1]=1;
    for (int i=1; i<=n; ++i) {
        for (int j=1; j<=m; ++j) {
            dp[i][j]=(dp[i-1][j] || dp[i][j-1]) && mat[i][j];
        }
    }
    dp[n+1][m]=1;
    for (int i=n; i>=1; --i) {
        for (int j=m; j>=1; --j) {
            dp[i][j]&=dp[i+1][j] || dp[i][j+1];
            cnt[i+j]+=dp[i][j];
        }
    }

    while (q--) {
        int x, y;
        scanf("%d %d", &x, &y);
//        ispis();
        if (!dp[x][y]) {
            mat[x][y]=0;
            printf("1\n");
            continue;
        }
        cnt[x+y]--;
        if (!cnt[x+y]) {
            cnt[x+y]++;
            printf("0\n");
            continue;
        }
        printf("1\n");
        dp[x][y]=0; mat[x][y]=0;
        bfs(x, y);
    }
}

void load() {
    scanf("%d %d", &n, &m);
    for (int i=1; i<=n; ++i) {
        for (int j=1; j<=m; ++j) {
            scanf("%d", &mat[i][j]);
            mat[i][j]^=1;
        }
    }
    scanf("%d", &q);
}

int main() {
    load();
    solve();
    return 0;
}

Compilation message (stderr)

furniture.cpp: In function 'void solve()':
furniture.cpp:74:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   74 |         scanf("%d %d", &x, &y);
      |         ~~~~~^~~~~~~~~~~~~~~~~
furniture.cpp: In function 'void load()':
furniture.cpp:94:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   94 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
furniture.cpp:97:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   97 |             scanf("%d", &mat[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~~~
furniture.cpp:101:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  101 |     scanf("%d", &q);
      |     ~~~~~^~~~~~~~~~

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