UVA 539 - The Settlers of Catan 解题报告

#include <iostream>
#include<cstring>
#include<algorithm>
#include<fstream>
#define maxn 30

using namespace std;

int map[maxn][maxn];
int vis[maxn][maxn];
int point_num;
int edge_num;
int max_num;

void dfs(int n,int num)
{
if(num>max_num) max_num=num;
for(int i=0;i<point_num;i++)
{
if(i!=n&&!vis
[i]&&map
[i])
{
vis
[i]=1;
vis[i]
=1;
dfs(i,num+1);
vis
[i]=0;
vis[i]
=0;
}
}
}
int main()
{
while(cin>>point_num>>edge_num)
{
if(0==point_num&&0==edge_num) break;
memset(map,0,sizeof(map));
memset(vis,0,sizeof(vis));
max_num=0;
for(int i=0;i<edge_num;i++)
{
int a,b;
cin>>a>>b;
map[a][b]=1;
map[b][a]=1;

}
for(int i=0;i<point_num;i++)
{
dfs(i,0);
}
cout<<max_num<<endl;
}
return 0;

}