uva 10171

求最短路徑的變化題，用了floyd

有一些特殊情況需要設置，然後就AC了

//============================================================================
// Name        : Meeting Prof. Miguel.cpp
// Date : 2013/3/24 下午10:22:31
// Author : GCA
//============================================================================
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <climits>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <cctype>
#include <utility>
using namespace std;
#ifdef ONLINE_JUDGE
#define ll "%lld"
#else
#define ll "%I64d"
#endif
typedef unsigned int uint;
typedef long long int Int;
#define Set(a,s) memset(a,s,sizeof(a))
#define Write(w) freopen(w,"w",stdout)
#define Read(r) freopen(r,"r",stdin)
#define Pln() printf("\n")
#define I_de(x,n)for(int i=0;i<n;i++)printf("%d ",x[i]);Pln()
#define De(x)printf(#x"%d\n",x)
#define For(i,x)for(int i=0;i<x;i++)
#define CON(x,y) x##y
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\
    printf("%d ",dp[htx][hty]);}Pln();}
#define M 30
#define PII pair<int,int>
#define PB push_back
#define oo (INT_MAX>>1)-2
#define Set_oo 0x3f
#define Is_debug true
#define debug(...) if(Is_debug)printf("DEBUG: "),printf(__VA_ARGS__)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define eps 1e-6
bool xdy(double x,double y){return x>y+eps;}
bool xddy(double x,double y){return x>y-eps;}
bool xcy(double x,double y){return x<y-eps;}
bool xcdy(double x,double y){return x<y+eps;}
int min3(int x,int y,int z){
    int tmp=min(x,y);
    return min(tmp,z);
}
int max3(int x,int y,int z){
    int tmp=max(x,y);
    return max(tmp,z);
}
int ymz[M][M];
int mmz[M][M];
char cms,cys;
int ms,ys;
int n,m;
void floyd(){
    for(int k=0;k<27;k++){
        for(int i=0;i<27;i++){
            for(int j=0;j<27;j++){
                if(ymz[i][k]+ymz[k][j]<ymz[i][j]){
                    ymz[i][j]=ymz[i][k]+ymz[k][j];
                }
            }
        }
    }
    for(int k=0;k<27;k++){
        for(int i=0;i<27;i++){
            for(int j=0;j<27;j++){
                if(mmz[i][k]+mmz[k][j]<mmz[i][j]){
                    mmz[i][j]=mmz[i][k]+mmz[k][j];
                }
            }
        }
    }
    int ans=oo;
    bool noway=true;
    for(int i=0;i<M;i++){
        if(ans>mmz[ms][i]+ymz[ys][i]){
            ans=mmz[ms][i]+ymz[ys][i];
            noway=false;
        }
    }
    if(noway)printf("You will never meet.\n");
    else{
        printf("%d",ans);
        for(int i=0;i<M;i++){
            char ctmp=i+'A';
            if(ans==mmz[ms][i]+ymz[ys][i])printf(" %c",ctmp);
        }Pln();
    }

}
int main() {
    ios_base::sync_with_stdio(0);
    while(~scanf("%d%*c",&m)&&m){
        char a,b,c,d;
        int w;
        fill(&ymz[0][0],&ymz[M-1][M-1],oo);
        fill(&mmz[0][0],&mmz[M-1][M-1],oo);
        for(int i=0;i<M;i++){
            ymz[i][i]=0;
            mmz[i][i]=0;
        }
        for(int i=0;i<m;i++){
            scanf("%c %c %c %c %d%*c",&a,&b,&c,&d,&w);
            if(a=='Y'){
                ymz[c-'A'][d-'A']=min(ymz[c-'A'][d-'A'],w);
                if(b=='B')ymz[d-'A'][c-'A']=min(ymz[d-'A'][c-'A'],w);
            }else{
                mmz[c-'A'][d-'A']=min(mmz[c-'A'][d-'A'],w);
                if(b=='B')mmz[d-'A'][c-'A']=min(mmz[d-'A'][c-'A'],w);
            }
        }

        scanf("%c %c%*c",&cys,&cms);
        ms=cms-'A';
        ys=cys-'A';
        floyd();
    }

}