백준 17086번 아기 상어 2 C++

https://www.acmicpc.net/problem/17086

17086번: 아기 상어 2

 

bfs

 

#include <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <algorithm>
#include <utility>
#include <stack>
#include <queue>
#include <math.h>
#include <set>
#include <map>
#include <list>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <limits.h>

using namespace std;
using int64 = long long;

int n, m;
int ans = 0;
int dRow[8] = { -1,-1,0,1,1,1,0,-1 };
int dCol[8] = { 0,1,1,1,0,-1,-1,-1 };

struct Info {
    int row;
    int col;
    int dist;
};

vector<vector<bool>> found;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    cin >> n >> m;
    found = vector<vector<bool>>(n, vector<bool>(m, false));
    queue<Info> q;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            int state;
            cin >> state;
            if (state == 1) {
                found[i][j] = true;
                q.push({ i,j,0 });
            }
        }
    }
    while (!q.empty()) {
        auto curr = q.front();
        q.pop();
        ans = max(ans, curr.dist);
        for (int i = 0; i < 8; i++) {
            int nextRow = curr.row + dRow[i];
            int nextCol = curr.col + dCol[i];
            if (nextRow < 0 || nextRow >= n) continue;
            if (nextCol < 0 || nextCol >= m) continue;
            if (found[nextRow][nextCol]) continue;
            found[nextRow][nextCol] = true;
            q.push({ nextRow,nextCol,curr.dist + 1 });
        }
    }
    cout << ans;
}