POJ 1251 Jungle Roads
传送门:http://poj.org/problem?id=1251
解题思路:简单的最小生成树
#include <iostream> #include <cstdio> #include <algorithm> #include <cstring> #include <cstdlib> using namespace std; const int maxn=28; struct Edge{ int u,v,w; bool operator <(const Edge &rhs) const{ return w<rhs.w; } }edges[maxn*maxn]; int f[maxn]; void init(int N){ for(int i=1;i<=N;i++) f[i]=i; } int findfa(int a){ if(f[a]!=a) f[a]=findfa(f[a]); return f[a]; } void unit(int a,int b){ int fa=findfa(f[a]); int fb=findfa(f[b]); if(fa!=fb) f[fa]=f[fb]; } int m=0; void addEdge(int u,int v,int w){ edges[m].u=u; edges[m].v=v; edges[m].w=w; m++; } int prime(int N){ init(N); sort(edges,edges+m); int ans=0; for(int i=0;i<m;i++){ if(findfa(edges[i].u)!=findfa(edges[i].v)){ ans+=edges[i].w; unit(edges[i].u,edges[i].v); } } return ans; } int main(){ int N; while(scanf("%d",&N)!=EOF&&N!=0){ m=0; for(int i=1;i<N;i++){ char s[3],e[3]; int t,w; scanf("%s",s); scanf("%d",&t); for(int k=0;k<t;k++){ scanf("%s",e); scanf("%d",&w); addEdge(s[0]-'A'+1,e[0]-'A'+1,w); } } printf("%d\n",prime(N)); } return 0; }
自己选的路,跪着也要把它走完------ACM坑