diff --git "a/khj20006/202502/21 BOJ P4 \353\266\200\354\202\260\354\235\230 \355\225\264\354\240\201.md" "b/khj20006/202502/21 BOJ P4 \353\266\200\354\202\260\354\235\230 \355\225\264\354\240\201.md" new file mode 100644 index 00000000..9de84f43 --- /dev/null +++ "b/khj20006/202502/21 BOJ P4 \353\266\200\354\202\260\354\235\230 \355\225\264\354\240\201.md" @@ -0,0 +1,64 @@ +```cpp + +#include +#include +#include +#include +using namespace std; + +int dx[4] = { 1,0,-1,0 }; +int dy[4] = { 0,1,0,-1 }; +int N, M, sx, sy; +char A[700][700]{}; +int L[700][700]{}, X[700][700]{}; + +int main() +{ + cin.tie(0)->sync_with_stdio(0); + + cin >> N >> M; + queue> Q; + bool vis[700][700]{}; + for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) { + cin >> A[i][j]; + if (A[i][j] == 'V') Q.emplace(i, j, 0), vis[i][j] = 1; + if (A[i][j] == 'Y') sx = i, sy = j; + } + + for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) X[i][j] = 2e9; + while (!Q.empty()) { + auto[x, y, t] = Q.front(); + Q.pop(); + X[x][y] = min(X[x][y], t); + for (int k = 0; k < 4; k++) { + int xx = x + dx[k], yy = y + dy[k]; + while (0 <= xx && xx < N && 0 <= yy && yy < M && A[xx][yy] != 'I') { + X[xx][yy] = min(X[xx][yy], t); + xx += dx[k], yy += dy[k]; + } + xx = x + dx[k], yy = y + dy[k]; + if (xx < 0 || xx >= N || yy < 0 || yy >= M || A[xx][yy] == 'I' || vis[xx][yy]) continue; + vis[xx][yy] = 1; + Q.emplace(xx, yy, t + 1); + } + } + + for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) vis[i][j] = 0; + vis[sx][sy] = 1; + Q.emplace(sx, sy, 0); + while (!Q.empty()) { + auto[x, y, t] = Q.front(); + Q.pop(); + if (A[x][y] == 'T') return cout << "YES", 0; + for (int k = 0; k < 4; k++) { + int xx = x + dx[k], yy = y + dy[k]; + if (xx < 0 || xx >= N || yy < 0 || yy >= M || A[xx][yy] == 'I' || vis[xx][yy] || t + 1 >= X[xx][yy]) continue; + Q.emplace(xx, yy, t + 1); + vis[xx][yy] = 1; + } + } + cout << "NO"; + +} + +```