#include <stdio.h>#include <queue>#include <iostream>#include <map>#include <string>using namespace std;#define INF 0xfffff //因为为了辨别是否有负权，所以INF不能开太大#define MAX 1100float dist[MAX], pre[MAX], path[MAX][MAX];bool sign[MAX];void initialize(int n) //初始化{ for(int i=1; i<=n; i++) { { //pre[i] = 0; dist[i] = 0; //将距离开始全变为最大 sign[i] = false; } for(int j=1; j<=n; j++) if(i == j) path[i][j] = 1.0; //图初始 else path[i][j] = 0; }}bool spfa(int n, int start) //无法计算负权{ /* for (int i=1; i<=n; ++i)//初始化 { dist[i] = INF; sign[i] = false; }*/ queue<int> Q; dist[start] = 1.0; sign[start] = true; Q.push(start); while (!Q.empty()) { int temp = Q.front(); Q.pop(); sign[temp] = false; for (int i=1; i<=n; ++i) { if (dist[temp] * path[temp][i] > dist[i])//存在负权的话，就需要创建一个COUNT数组，当某点的入队次数超过V(顶点数)返回。 { dist[i] = dist[temp] * path[temp][i]; if (!sign[i]) { Q.push(i); sign[i] = true; } if( dist[start] > 1.0) return true; } } } return false;}void input(int line){ map<string, int>list; for(int i=1; i<=line; i++) { string temp; cin >> temp; list[temp] = i; } int count; scanf("%d", &count); string a, b; float weight; for(int i=0; i<count; i++) { cin >> a >> weight >> b; //if(path[list[a]][list[b]] > weight) //有多条路，保存最短的那条 { path[list[a]][list[b]] = weight; //path[list[b]][list[a]] = weight; //无向图双向 } }}int main(){ int n, T=0; while(~scanf("%d", &n) && n ) { initialize(n); input(n); int flag =1; for(int i=1; i<=n; i++) { if(spfa(n, i) ) {printf("Case %d: Yes
", ++T); flag = 0; break;} } if(flag) {printf("Case %d: No
", ++T); } } return 0; }