标签：
Time Limit: 1 Sec Memory Limit: 256 MB
http://poj.org/problem?id=1466
In the second year of the university somebody started a study on the romantic relations between the students. The relation "romantically involved" is defined between one girl and one boy. For the study reasons it is necessary to find out the maximum set satisfying the condition: there are no two students in the set who have been "romantically involved". The result of the program is the number of students in such a set.
For each given data set, the program should write to standard output a line containing the result.
要求找到一个点集合，让这个集合中并没有人互相喜欢
找相互喜欢的人的最大匹配，答案为总人数-匹配数/2
做的时候又忘了数据初始化，悲伤
1 #include<iostream> 2 #include<cstdio> 3 #include<algorithm> 4 #include<cmath> 5 #include<cstring> 6 #include<queue> 7 #include<vector> 8 using namespace std; 9 const int mxn=800; 10 int n; 11 vector<int>mp[mxn]; 12 int vis[mxn]; 13 int mc[mxn]; 14 int x; 15 inline int read(){ 16 int x=0; 17 char ch=getchar(); 18 while(ch<‘0‘||ch>‘9‘)ch=getchar(); 19 while(ch>=‘0‘ && ch<=‘9‘){ x=x*10+ch-‘0‘;ch=getchar(); } 20 return x; 21 } 22 int dfs(int u){ 23 for(int i=0;i<mp[u].size();i++){ 24 int v=mp[u][i]; 25 if(!vis[v]){ 26 vis[v]=1; 27 if(mc[v]==-1 || dfs(mc[v])){ 28 mc[v]=u; 29 return 1; 30 } 31 } 32 } 33 return 0; 34 } 35 int Maxmatch(){ 36 int res=0; 37 memset(mc,-1,sizeof(mc)); 38 int i; 39 for(i=0;i<n;i++){ 40 { 41 memset(vis,0,sizeof(vis)); 42 res+=dfs(i); 43 } 44 } 45 return res; 46 } 47 int main(){ 48 while(scanf("%d",&n)!=EOF){ 49 //read 50 for(int i=0;i<=n;i++) mp[i].clear(); 51 for(int L=1;L<=n;L++){ 52 int u,v; 53 u=read(); 54 int i,j; 55 x=read(); 56 for(i=0;i<x;i++){ 57 v=read(); 58 mp[u].push_back(v); 59 } 60 } 61 //read finished 62 int ans=Maxmatch(); 63 printf("%d\n",n-ans/2); 64 } 65 return 0; 66 }
标签：
原文地址：http://www.cnblogs.com/SilverNebula/p/5604620.html
