백준 14940번 쉬운 최단거리 C++

https://www.acmicpc.net/problem/14940

14940번: 쉬운 최단거리

 

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; 

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

int dRow[4] = { -1,0,1,0 };
int dCol[4] = { 0,1,0,-1 };

int n, m;
vector<vector<int>> board;
vector<vector<int>> resultBoard;
vector<vector<bool>> found;

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

    cin >> n >> m;
    board = vector<vector<int>>(n, vector<int>(m));
    resultBoard = vector<vector<int>>(n, vector<int>(m, -1));
    found = vector<vector<bool>>(n, vector<bool>(m, false));

    pair<int, int> startPos;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cin >> board[i][j];
            if (board[i][j] == 0) resultBoard[i][j] = 0;
            if (board[i][j] == 2) startPos = { i,j };
        }
    }
    queue<Info> q;
    q.push({ startPos.first,startPos.second,0 });
    found[startPos.first][startPos.second] = true;
    while (!q.empty()) {
        auto curr = q.front();
        q.pop();
        resultBoard[curr.row][curr.col] = curr.moveCnt;
        for (int i = 0; i < 4; 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 (board[nextRow][nextCol] == 0) continue;
            if (found[nextRow][nextCol]) continue;
            found[nextRow][nextCol] = true;
            q.push({ nextRow,nextCol,curr.moveCnt + 1 });
        }
    }
    for (auto a : resultBoard) {
        for (auto b : a) {
            cout << b << " ";
        }
        cout << "\n";
    }
}