AcWing2060. 奶牛选美

代码

#include<iostream>
#include<cstring>
#include<algorithm>
#include<vector>

//flood fill algorithm
//曼哈顿距离
//dfs
#define x first
#define y second
using namespace std;

const int N = 55;
typedef pair<int ,int > PII;


char g[N][N];
int dx[]={-1,0,1,0},dy[]={0,1,0,-1};

vector<PII>points[2];//二维数组,因为一共只有两个斑点

int n,m;

void dfs(int x,int y,vector<PII>& ps)
{
    g[x][y]='.';
    ps.push_back({x,y});
    for(int i = 0; i < 4; i++)//对于每个点枚举四个方向
    {
        int a = x + dx[i], b = y + dy[i];
       // if(g[a][b] == 'X')
       if(a>= 0 && a<n && b>=0 && b< m&& g[a][b]=='X')//在图内并且该点还为‘X’
        dfs(a, b, ps);
    }

}

int main()
{

    cin>>n>>m;

    for(int i = 0 ; i < n ; i ++) cin>> g[i];

    for(int i = 0 , k = 0; i < n; i++)
    {
        for(int j = 0 ; j < m; j++)
        {
            if(g[i][j] == 'X')
            dfs(i,j,points[k++]);
        }
    }

    int res = 1e8;
/*
    for(int i = 0 ; i<points[0].size(); i++)
    {
        for(int j = 0; j<points[1].size(); j++)
        {
            res = min(res, abs(points[0][i].x-points[1][j].x)+abs(points[0][i].y-points[1][j].y)-1);
        }
    }
    */
    for (auto& a: points[0])
        for (auto& b: points[1])
            res = min(res, abs(a.x - b.x) + abs(a.y - b.y) - 1);
    cout << res << endl;
    return 0;
}