백준 16924번 십자가 찾기 C++

https://www.acmicpc.net/problem/16924

16924번: 십자가 찾기

 

모든 격자판을 탐색하면서 *을 만나면 4방향으로 탐색해서 4방향중 가장 작은 거리가 그 *에서 그릴 수 있는 가장 큰 십자가이다.

 

#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;

enum class Dir {
    UP,
    RIGHT,
    DOWN,
    LEFT,
};

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

int n, m;
vector<Info> ans;
int dRow[4] = { -1,0,1,0 };
int dCol[4] = { 0,1,0,-1 };

vector<vector<char>> board;
vector<vector<bool>> visited;

int GetCrossCnt(int row, int col, Dir dir) {
    int ret = 0;
    while (true) {
        row += dRow[(int)dir];
        col += dCol[(int)dir];
        if (row <= 0 || row > n) break;
        if (col <= 0 || col > m) break;
        if (board[row][col] == '.') break;
        ret++;
    }
    return ret;
}

void SetVisited(int row, int col, int dist) {
    visited[row][col] = true;
    for (int i = 0; i < 4; i++) {
        int nextRow = row;
        int nextCol = col;
        for (int j = 1; j <= dist; j++) {
            nextRow += dRow[i];
            nextCol += dCol[i];
            visited[nextRow][nextCol] = true;
        }
    }
}

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

    cin >> n >> m;
    board = vector<vector<char>>(n + 1, vector<char>(m + 1));
    visited = vector<vector<bool>>(n + 1, vector<bool>(m + 1, false));
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            cin >> board[i][j];
        }
    }
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            if (board[i][j] == '.') continue;
            int up = GetCrossCnt(i, j, Dir::UP);
            int right = GetCrossCnt(i, j, Dir::RIGHT);
            int down = GetCrossCnt(i, j, Dir::DOWN);
            int left = GetCrossCnt(i, j, Dir::LEFT);
            int minVal = min(up, min(right, min(down, left)));
            if (minVal == 0) continue;
            for (int k = 1; k <= minVal; k++) {
                ans.push_back({ i,j,k });
            }
            SetVisited(i, j, minVal);
        }
    }
    bool isAns = true;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            if (board[i][j] == '.') continue;
            if (visited[i][j]) continue;
            isAns = false;
        }
    }
    if (isAns == false) cout << -1;
    else {
        cout << ans.size() << "\n";
        for (auto a : ans) {
            cout << a.row << " " << a.col << " " << a.size << "\n";
        }
    }
}