USACO:Bessie Come Home

/*ID: Jang LawrencePROG: comehomeLANG: C++*/#include<iostream>#include<cstring>#include<cstdio>#include<algorithm>#include<queue>#include<cmath>#define X first#define Y second#define sqr(a) ((a)*(a))using namespace std;typedef long long lng;int n;typedef pair<int,int> pii;int d[52][52];int s_(char c){if(c<='Z'&&c>='A') return 25+c-'A'+1;else return c-'a';}bool in[52];int dis[52];void f(){    for(int i=0;i<51;++i)    dis[i]=100000000;    dis[51]=0;    bool vis[52]={}; for(int i=0;i<52;++i) {     int mi=100000000,v;     for(int j=0;j<52;++j)     if(!vis[j]&&mi>dis[j]) mi=dis[v=j];     vis[v]=1;     for(int j=0;j<52;++j)     if(d[v][j]!=-1&&!vis[j]&&dis[j]>dis[v]+d[v][j])     {         dis[j]=dis[v]+d[v][j];     } }}int main(){  #ifndef  DEBUG  freopen("comehome.in","r",stdin);  freopen("comehome.out","w",stdout);  #endifscanf("%d",&n);memset(d,-1,sizeof(d));for(int i=0;i<n;++i){    getchar();    char x,y;    int di;    scanf("%c %c %d",&x,&y,&di);    int j=s_(x),k=s_(y);  if(d[j][k]==-1)  d[j][k]=d[k][j]=di;  else  d[j][k]=d[k][j]=(di<d[j][k])?di:d[j][k];    if(j>25) in[j]=1;    if(k>25) in[k]=1;}f();int  ans=100000000,ansid;for(int i=26;i<51;++i)if(in[i]&&ans>dis[i]) ans=dis[ansid=i];printf("%c %d\n",char('A'+ansid-26),ans);    return 0;}