A Plug for UNIX（网络流模板题）

来源：互联网发布：同方云计算战略发布会编辑：程序博客网时间：2024/06/16 14:36
只是单纯的为了存模板 = =!
#include<map>#include<vector>#include<set>#include<string>#include<queue>#include<stack>#include<cstdio>#include<iostream>#include<cstring>#include<algorithm>using namespace std;const int  INF = 1111111111;const int maxn = 444;const int maxd = 111111;int nn,mm,kk,cnt;int floyd[maxn][maxn];int array[maxn];    //设备插头数组int array2[maxn];   //插座数组map<string,int>idm; //插座编码vector<string>idv;  //插座数组//-------------------------网络流模板---------------------------struct Edge{    int from,to,cap,flow;//容量 流量    Edge(int u,int v,int c,int f):from(u),to(v),cap(c),flow(f){};};struct EdmondsKarp{    int n,m;    vector<Edge>edges;    vector<int>G[maxn]; //结点i的第j条边是编号多少    int a[maxn];        //起点到i的可改进量    int p[maxn];    void init(int n){        for(int i = 0; i < n; i++) G[i].clear();        edges.clear();    }    void AddEdge(int from,int to,int cap){        edges.push_back(Edge(from,to,cap,0));        edges.push_back(Edge(to,from,0,0)); //反向弧        m = edges.size();        G[from].push_back(m  - 2);        G[to].push_back(m - 1);    }    int Maxflow(int s,int t){        int flow = 0;        while(true){            memset(a,0,sizeof(a));            queue<int>Q;            Q.push(s);                          //加入起点            a[s] = INF;            while(!Q.empty()){                int x = Q.front(); Q.pop();                for(int i = 0; i < G[x].size(); i++){                    Edge &e = edges[G[x][i]];                    if(!a[e.to] && e.cap > e.flow){                        p[e.to] = G[x][i];      //                        a[e.to] = min(a[x],e.cap - e.flow);                        Q.push(e.to);                    }                }                if(a[t]) break;            }            if(!a[t]) break;            for(int u = t; u != s; u = edges[p[u]].from){                edges[p[u]].flow += a[t];                edges[p[u]^1].flow -= a[t];            }            flow += a[t];        }        return flow;    }}edm;//------------------------------------------------------------void debug(){    for(int i = 0; i < idv.size(); i++)        cout << idv[i] << endl;    for(int i = 1; i < cnt; i++){        for(int j = 1; j < cnt; j++)            printf("%d ",floyd[i][j]);        puts("");    }    for(int i = 0; i < nn; i++)        printf("%d ",array2[i]);    puts("");    for(int i = 0; i < mm; i++)        printf("%d ",array[i]);    puts("");}void Floyd(){       //利用F loyd判断重复    for(int i = 1; i < cnt; i++) floyd[i][i] = 1;    for(int k = 1; k < cnt; k++)        for(int i = 1; i < cnt; i++)            for(int j = 1; j < cnt; j++){                if(floyd[i][k] && floyd[k][j])                    floyd[i][j] = 1;            }}void solve(){    for(int i = 0; i < mm; i++){        //插座        for(int j = 0; j < nn; j++){    //插头            int e1 = array[i],e2 = array2[j];            if(floyd[e1][e2]){                //printf("%d %d\n",i + 1,mm + 1 + j);                edm.AddEdge(i + 1,mm + 1 + j,INF);            }        }    }    for(int i = 0; i < mm; i++){        //printf("0 %d\n",i + 1);        edm.AddEdge(0,i + 1,1);    }    for(int i = 0; i < nn; i++){        //printf("%d %d\n",mm + 1 + i,nn + mm + 1);        edm.AddEdge(mm + 1 + i,nn + mm + 1,1);    }    int ff = edm.Maxflow(0,nn + mm + 1);    printf("%d\n",mm - ff);}int main(){    int T;    char str[30],str2[30];    scanf("%d",&T);    while(T--){        memset(floyd,0,sizeof(floyd));      //init        edm.init(422);        cnt = 1;        idm.clear();        idv.clear();        scanf("%d",&nn);                     //插座        for(int i = 0; i < nn; i++){            scanf("%s",str);            string sstr(str);            if(!idm[sstr]){                idv.push_back(str);                idm[sstr] = cnt++;            }            array2[i] = idm[sstr];        }        scanf("%d",&mm);                     //插头        for(int i = 0; i < mm; i++){            scanf("%*s%s",str);            string sstr(str);            if(!idm[sstr]){                idv.push_back(str);                idm[sstr] = cnt++;            }            array[i] = idm[sstr];        }        scanf("%d",&kk);        for(int i = 0; i < kk; i++){            scanf("%s%s",str,str2);            string sstr1(str),sstr2(str2);            if(!idm[sstr1]){                idv.push_back(sstr1);                idm[sstr1] = cnt++;            }            if(!idm[sstr2]){                idv.push_back(sstr2);                idm[sstr2] = cnt++;            }            int e1 = idm[sstr1],e2 = idm[sstr2];            floyd[e1][e2] = 1;            //printf("%d %d\n",e1,e2);        }        Floyd();        //debug();        solve();        if(T) puts("");    }    return 0;}
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