hdu 2094

来源：互联网发布：北京编程培训学校编辑：程序博客网时间：2024/06/02 04:12

好气

#include <stdio.h>#include <algorithm>#include <math.h>#include <string.h>#include <vector>#include <queue>#include <map>#include <stack>#include <iostream>#define pi acos(-1.0)#define INF 0x3f3f3f3fusing namespace std;#define ll long longmap<string,int> mp;const int maxn=1010;vector<int> e[maxn];int deg[maxn];int  main(){    freopen("C:\\Users\\Administrator\\Desktop\\a.txt","r",stdin);    //ios::sync_with_stdio(false);    //freopen("C:\\Users\\Administrator\\Desktop\\b.txt","w",stdout);    int n;    while(scanf("%d",&n),n)    {        mp.clear();        for(int i=0;i<=maxn;i++) e[i].clear();        memset(deg,0,sizeof deg);        char c1[maxn],c2[maxn]; int tot=0;        for(int i=0;i<n;i++)        {            scanf("%s",c1); if(!mp[c1]) mp[c1]=++tot;            scanf("%s",c2); if(!mp[c2]) mp[c2]=++tot;            int a=mp[c1],b=mp[c2];            e[a].push_back(b);            deg[b]++;        }        int cnt=0;        for(int i=1;i<=tot;i++)            if(deg[i]==0)                cnt++;        if(cnt!=1) printf("No\n");        else  printf("Yes\n");    }    return 0;}

阅读全文

0 0