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Time Limit: 5000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 2997 Accepted Submission(s): 913
#include <cstdio> #include <cstring> #include <queue> #include <algorithm> #include <stdlib.h> using namespace std; const int N = 400; const int INF = 999999999; int lx[N],ly[N]; bool visitx[N],visity[N]; int slack[N]; int match[N]; int graph[N][N]; int idx[N]; ///船所在的油井下标 int n,m,k,p; bool Hungary(int u) { visitx[u] = true; for(int i=m+1; i<=m+n; i++) { if(!visity[i]) { int temp = lx[u]+ly[i]-graph[u][i]; if(temp==0) { visity[i] = true; if(match[i]==-1||Hungary(match[i])) { match[i] = u; return true; } } else { slack[i] = min(slack[i],temp); } } } return false; } void KM() { memset(match,-1,sizeof(match)); memset(ly,0,sizeof(ly)); for(int i=1; i<=n; i++) ///定标初始化 { lx[idx[i]] = -INF; } for(int i=1; i<=n; i++) { for(int j=m+1; j<=n+m; j++) { lx[idx[i]] = max(lx[idx[i]],graph[idx[i]][j]); } } for(int i=1; i<=n; i++) { for(int j=m+1; j<=m+n; j++) slack[j] = INF; while(true) { memset(visitx,false,sizeof(visitx)); memset(visity,false,sizeof(visity)); if(Hungary(idx[i])) break; else { int temp = INF; for(int j=1+m; j<=n+m; j++) { if(!visity[j]) temp = min(temp,slack[j]); } for(int j=1; j<=n; j++) { if(visitx[idx[j]]) lx[idx[j]]-=temp; } for(int j=1; j<=n+m; j++) { if(visity[j]) ly[j]+=temp; else slack[j]-=temp; } } } } } struct Edge { int v,w,next; } edge[N*N]; int head[N],tot; void init() { memset(head,-1,sizeof(head)); tot = 0; } void addEdge(int u,int v,int w,int &k) { edge[k].v = v,edge[k].w = w,edge[k].next = head[u],head[u] = k++; } int low[N]; bool vis[N]; void spfa(int s) { for(int i=1; i<=n+m; i++) { low[i] = INF; vis[i] = false; } queue<int> q; low[s] = 0; q.push(s); while(!q.empty()) { int u = q.front(); q.pop(); vis[u] = false; for(int i=head[u]; i!=-1; i=edge[i].next) { int v = edge[i].v,w = edge[i].w; if(low[v]>low[u]+w) { low[v] = low[u]+w; if(!vis[v]) { vis[v] = true; q.push(v); } } } } for(int i=1+m; i<=n+m; i++) { if(low[i]!=INF) { graph[s][i] = -low[i]; } } } int main() { while(scanf("%d%d%d%d",&n,&m,&k,&p)!=EOF) { init(); for(int i=1; i<=n; i++) { scanf("%d",&idx[i]); } /**油田 1-m,港口 m+1-m+n*/ for(int i=1; i<=k; i++) { int u,v,w; scanf("%d%d%d",&u,&v,&w); addEdge(u,v,w,tot); addEdge(v,u,w,tot); } for(int i=1; i<=p; i++) { int u,v,w; scanf("%d%d%d",&u,&v,&w); addEdge(v,u+m,w,tot); ///油井向港口添加单向边 } memset(graph,0,sizeof(graph)); for(int i=1; i<=n; i++) { spfa(idx[i]); } KM(); int ans = 0; for(int i=1+m; i<=n+m; i++) { if(match[i]!=-1) { ans+=graph[match[i]][i]; } } printf("%d\n",-ans); } }
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原文地址:http://www.cnblogs.com/liyinggang/p/5734502.html