Submission #436876

#	Time	Username	Problem	Language	Result	Execution time	Memory
436876		qwerasdfzxcl	Sandwich (JOI16_sandwich)	C++14	35 / 100	8061 ms	44364 KiB

sandwich

#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
struct vertex{
    int x, y, z;
    vertex(){}
    vertex(int _x, int _y, int _z): x(_x), y(_y), z(_z) {}
};
vector<vertex> adj[404][404][2];
char matrix[404][404];
bool visited[404][404][2];
int deg[404][404][2], dp[404][404][2], dx[4] = {-1, 1, 0, 0}, dy[4] = {0, 0, 1, -1}, n, m;

bool valid(int x, int y){
    return ((1<=x && x<=n) && (1<=y && y<=m));
}

int count_visited(){
    int ret = 0, cnt = 0;
    queue<vertex> q;
    for (int i=1;i<=n;i++){
        for (int j=1;j<=m;j++){
            if (visited[i][j][0] || visited[i][j][1]) ret++;
            if (visited[i][j][0] && !deg[i][j][0]) q.push(vertex(i, j, 0));
            if (visited[i][j][1] && !deg[i][j][1]) q.push(vertex(i, j, 1));
        }
    }
    while(!q.empty()){
        auto v = q.front(); q.pop();
        //printf("%d %d %d\n", v.x, v.y, v.z);
        cnt++;
        for (auto &w:adj[v.x][v.y][v.z]){
            deg[w.x][w.y][w.z]--;
            if (!deg[w.x][w.y][w.z]) q.push(w);
        }
    }
    //printf("%d %d\n", ret, cnt);
    if (ret==cnt) return ret*2;
    return 1e9;
}

void dfs(int x, int y, int c){
    if (visited[x][y][c]) return;
    visited[x][y][c] = 1;
    int nx1 = x+dx[c], nx2 = y+dy[c];
    if (valid(nx1, nx2)){
        adj[x][y][c].emplace_back(nx1, nx2, c);
        deg[nx1][nx2][c]++;
        dfs(nx1, nx2, c);
    }
    int d = 2;
    if (!c && matrix[x][y]=='Z') d = 3;
    if (c && matrix[x][y]=='N') d = 3;
    int nx3 = x+dx[d], nx4 = y+dy[d];
    if (valid(nx3, nx4)){
        adj[x][y][c].emplace_back(nx3, nx4, 0);
        if (d==2 && matrix[nx3][nx4]=='N'){
            deg[nx3][nx4][0]++;
            dfs(nx3, nx4, 0);
        }
        else if (d==3 && matrix[nx3][nx4]=='Z'){
            deg[nx3][nx4][0]++;
            dfs(nx3, nx4, 0);
        }
        else{
            deg[nx3][nx4][1]++, adj[x][y][c].back().z = 1;
            dfs(nx3, nx4, 1);
        }
    }
}

void init(){
    for (int i=1;i<=n;i++){
        for (int j=1;j<=m;j++){
            visited[i][j][0] = visited[i][j][1] = 0;
            deg[i][j][0] = deg[i][j][1] = 0;
            adj[i][j][0].clear();
            adj[i][j][1].clear();
        }
    }
}

int main(){
    scanf("%d %d", &n, &m);
    for (int i=1;i<=n;i++){
        scanf("%s", matrix[i]+1);
        for (int j=1;j<=m;j++) dp[i][j][0] = dp[i][j][1] = 1e9;
    }
    for (int i=1;i<=n;i++){
        for (int j=1;j<=m;j++){
            init(); dfs(i, j, 0);
            dp[i][j][0] = count_visited();
            init(); dfs(i, j, 1);
            dp[i][j][1] = count_visited();
            //printf("%d %d: %d %d\n", i, j, dp[i][j][0], dp[i][j][1]);
        }
    }
    for (int i=1;i<=n;i++){
        for (int j=1;j<=m;j++){
            int ans = min(dp[i][j][0], dp[i][j][1]);
            if (ans==1e9) ans = -1;
            printf("%d ", ans);
        }
        printf("\n");
    }
    return 0;
}

Compilation message (stderr)

sandwich.cpp: In function 'int main()':
sandwich.cpp:85:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
sandwich.cpp:87:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |         scanf("%s", matrix[i]+1);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 35 / 35
• Subtask 2: 0 / 65