제출 #1279913

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1279913		ducanh0811	Tracks in the Snow (BOI13_tracks)	C++20	4.38 / 100	1539 ms	934116 KiB

tracks

#include <bits/stdc++.h>
#define int long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define REV(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
using namespace std;

int n, m;
#define MAXN 4005
char a[MAXN][MAXN];

const int dx[] = {0, 1, 0, -1};
const int dy[] = {-1, 0, 1, 0};

bool start[MAXN][MAXN];
bool vi[MAXN][MAXN];
int group = 0;

bool valid(int i, int j){
    return (i >= 1 && i <= n && j >= 1 && j <= m);
}

void DFS(int i, int j){
    start[i][j] = 1;
    FOR(k, 0, 3){
        int ii = i + dy[k];
        int jj = j + dx[k];
        if (valid(ii, jj) && a[ii][jj] == a[1][1] && start[ii][jj] == 0){
            DFS(ii, jj);
        }
    }
}

void dfs(int i, int j){
    vi[i][j] = 1;
    FOR(k, 0, 3){
        int ii = i + dy[k];
        int jj = j + dx[k];
        if (valid(ii, jj) && !vi[ii][jj] && (a[ii][jj] == a[i][j] || start[ii][jj] || start[i][j])){
            dfs(ii, jj);
        }
    }
}

void solve(){
    cin >> n >> m;
    FOR(i, 1, n){
        FOR(j, 1, m){
            cin >> a[i][j];
        }
    }
    DFS(1, 1);
//    FOR(i, 1, n){
//        FOR(j, 1, m){
//            cout << start[i][j];
//        }
//        cout << '\n';
//    }
    FOR(i, 1, n){
        FOR(j, 1, m){
            if (vi[i][j]) continue;
            group++;
            dfs(i, j);
        }
    }
    int ok = 0;
    FOR(i, 1, n){
        FOR(j, 1, m){
            if (start[i][j]){
                FOR(k, 0, 3){
                    int ii = i + dy[k];
                    int jj = j + dx[k];
                    if (valid(ii, jj) && a[ii][jj] != '.' && a[ii][jj] != a[i][j]) ok = 1;
                }
            }
        }
    }
    cout << group + ok;
}

#define task "test"
int32_t main(){
    if (fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
    solve();
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

tracks.cpp: In function 'int32_t main()':
tracks.cpp:83:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   83 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:84:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   84 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 30
• Subtask 2: 4.375 / 70