1 Source Code
  2 Problem: 2125        User: sdfzyhy
  3 Memory: 848K        Time: 79MS
  4 Language: G++        Result: Accepted
  5 
  6     Source Code
  7 
  8     //BZOJ 2125
  9     #include<vector>
 10     #include<cstdio>
 11     #include<cstring>
 12     #include<cstdlib>
 13     #include<iostream>
 14     #include<algorithm>
 15     #define rep(i,n) for(int i=0;i<n;++i)
 16     #define F(i,j,n) for(int i=j;i<=n;++i)
 17     #define D(i,j,n) for(int i=j;i>=n;--i)
 18     #define fore(i,x) for(int i=head[x];i;i=next[i])
 19     #define pb push_back
 20     using namespace std;
 21     inline int getint(){
 22         int v=0,sign=1; char ch=getchar();
 23         while(ch<‘0‘||ch>‘9‘){ if (ch==‘-‘) sign=-1; ch=getchar();}
 24         while(ch>=‘0‘&&ch<=‘9‘){ v=v*10+ch-‘0‘; ch=getchar();}
 25         return v*sign;
 26     }
 27     const int N=310,M=20010,INF=~0u>>2;
 28     typedef long long LL;
 29     /******************tamplate*********************/
 30 
 31     struct edge{
 32         int from,to,v;
 33     };
 34     int n,m;
 35     struct Net{
 36         edge E[M];
 37         int head[N],next[M],cnt;
 38         void add(int x,int y,int z){
 39             E[++cnt]=(edge){x,y,z};
 40             next[cnt]=head[x]; head[x]=cnt;
 41             E[++cnt]=(edge){y,x,0};
 42             next[cnt]=head[y]; head[y]=cnt;
 43         }
 44         int s,t,d[N],cur[N],Q[N];
 45         void init(){
 46             n=getint(); m=getint();
 47             s=0; t=n*2+1; cnt=1;
 48             int x,y;
 49             F(i,1,n){
 50                 x=getint();
 51                 add(i+n,t,x);
 52             }
 53             F(i,1,n){
 54                 x=getint();
 55                 add(s,i,x);
 56             }
 57             F(i,1,m){
 58                 x=getint(); y=getint();
 59                 add(x,y+n,INF);
 60             }
 61         }
 62         bool mklevel(){
 63             memset(d,-1,sizeof d);
 64             d[s]=0;
 65             int l=0,r=-1;
 66             Q[++r]=s;
 67             while(l<=r){
 68                 int x=Q[l++];
 69                 fore(i,x){
 70                     edge&e=E[i];
 71                     if (d[e.to]==-1 && e.v>0){
 72                         d[e.to]=d[x]+1;
 73                         Q[++r]=e.to;
 74                     }
 75                 }
 76             }
 77             return d[t]!=-1;
 78         }
 79         int dfs(int x,int a){
 80             if (x==t) return a;
 81             int flow=0;
 82             for(int &i=cur[x];i && flow<a;i=next[i]){
 83                 edge&e=E[i];
 84                 if (!e.v || d[e.to]!=d[x]+1) continue;
 85                 int f=dfs(e.to,min(a-flow,e.v));
 86                 if (f>0){
 87                     flow+=f;
 88                     e.v-=f;
 89                     E[i^1].v+=f;
 90                 }
 91             }
 92             if (!flow) d[x]=-1;
 93             return flow;
 94         }
 95         int Dinic(){
 96             int flow=0;
 97             while(mklevel()){
 98                 F(i,s,t) cur[i]=head[i];
 99                 flow+=dfs(s,INF);
100             }
101             return flow;
102         }
103         bool vis[N];
104         void dfs1(int x){
105             if (vis[x]) return;
106             vis[x]=1;
107             for(int i=head[x];i;i=next[i])
108                 if (E[i].v) dfs1(E[i].to);
109         }
110         void solve(){
111             printf("%d\n",Dinic());
112             int num=0;
113             memset(vis,0,sizeof vis);
114             dfs1(s);
115             F(i,1,n) num+=(!vis[i])+vis[i+n];
116             printf("%d\n",num);
117             F(i,1,n){
118                 if (!vis[i]) printf("%d -\n",i);
119                 if (vis[i+n]) printf("%d +\n",i);
120             }
121         }
122     }G1;
123 
124     int main(){
125     #ifndef ONLINE_JUDGE
126         freopen("2125.in","r",stdin);
127         freopen("2125.out","w",stdout);
128     #endif
129         G1.init();
130         G1.solve();
131         return 0;
132     }