POJ 3620 Avoid The Lakes(DFS)

标签：dfs   poj   

题目链接:http://poj.org/problem?id=3620

DFS基础题~

#include<cstdio>
#include<iostream>
#include<sstream>
#include<cstdlib>
#include<cstring>
#include<string>
#include<climits>
#include<cmath>
#include<algorithm>
#include<queue>
#include<vector>
#include<stack>
#include<set>
using namespace std;
#define maxn 100+5
#define INF 0x3f3f3f3f
int n,m,k,fi,fj,sum;
int map[maxn][maxn],vis[maxn][maxn];
int dir[4][2]= {0,1,0,-1,1,0,-1,0};
bool find()
{
    for(int i=1; i<=n; i++)
        for(int j=1; j<=m; j++)
            if(map[i][j]&&!vis[i][j])
            {
                fi=i;
                fj=j;
                return 1;
            }
    return 0;
}
void DFS(int i,int j)
{
    for(int k=0; k<4; k++)
    {
        int a = i + dir[k][0];
        int b = j + dir[k][1];
        if( a>=1 && a<=n && b>=1 && b<=m && !vis[a][b] && map[a][b] )
        {
            vis[a][b] = 1;
            DFS(a,b);
            sum++;
        }
    }
}
int main()
{
    int i,j;
    while(~scanf("%d%d%d",&n,&m,&k))
    {
        memset(map,0,sizeof(map));
        memset(vis,0,sizeof(vis));
        int a,b;
        for(i=1; i<=k; i++)
        {
            scanf("%d%d",&a,&b);
            map[a][b]=1;
        }
        int result=-INF;
        while(find())
        {
            vis[fi][fj]=1;
            sum=1;
            DFS(fi,fj);
            result=max(result,sum);
        }
        printf("%d\n",result);
    }
    return 0;
}

POJ 3620 Avoid The Lakes(DFS)

标签：dfs   poj   

原文地址：http://blog.csdn.net/qq_30076791/article/details/47754739