1 #include <queue>
  2 #include <cstdio>
  3 #include <cstring>
  4 #include <cstdlib>
  5 #include <iostream>
  6 #include <algorithm>
  7 
  8 const int MAXV=110;
  9 const int MAXE=10010;
 10 const int INF=0x7FFFFFFF;
 11 
 12 struct Edge{
 13     int from;
 14     int to;
 15     int flow;
 16     Edge* rev;
 17     Edge* next;
 18 };
 19 Edge E[MAXE];
 20 Edge* head[MAXV];
 21 Edge* top=E;
 22 
 23 int v;
 24 int depth[MAXV];
 25 int flow[MAXV][MAXV];
 26 
 27 int Dinic(int,int);
 28 void Initialize();
 29 void Insert(int,int);
 30 int DFS(int,int,int);
 31 bool BFS(int,int);
 32 
 33 int main(){
 34     freopen("maxflowa.in","r",stdin);
 35     freopen("maxflowa.out","w",stdout);
 36     Initialize();
 37     printf("%d\n",Dinic(1,v));
 38     return 0;
 39 }
 40 
 41 int Dinic(int s,int t){
 42     int ans=0;
 43     while(BFS(s,t)){
 44         ans+=DFS(s,INF,t);
 45     }
 46     return ans;
 47 }
 48 
 49 int DFS(int s,int flow,int t){
 50     if(s==t||flow==0)
 51         return flow;
 52     int tmp=flow;
 53     int k;
 54     for(Edge* i=head[s];i!=NULL;i=i->next){
 55         if(i->flow!=0&&tmp!=0&&depth[i->to]==depth[s]+1){
 56             k=DFS(i->to,std::min(tmp,i->flow),t);
 57             if(k==0){
 58                 depth[i->to]=0;
 59                 continue;
 60             }
 61             tmp-=k;
 62             i->flow-=k;
 63             i->rev->flow+=k;
 64             if(tmp==0)
 65                 break;
 66         }
 67     }
 68     return flow-tmp;
 69 }
 70 
 71 bool BFS(int s,int t){
 72     memset(depth,0,sizeof(depth));
 73     std::queue<int> q;
 74     depth[s]=1;
 75     q.push(s);
 76     while(!q.empty()){
 77         s=q.front();
 78         q.pop();
 79         for(Edge* i=head[s];i!=NULL;i=i->next){
 80             if(depth[i->to]==0&&i->flow!=0){
 81                 q.push(i->to);
 82                 depth[i->to]=depth[s]+1;
 83                 if(i->to==t)
 84                     return true;
 85             }
 86         }
 87     }
 88     return false;
 89 }
 90 
 91 void Initialize(){
 92     scanf("%d",&v);
 93     for(int i=1;i<=v;i++){
 94         for(int j=1;j<=v;j++){
 95             scanf("%d",&flow[i][j]);
 96         }
 97     }
 98     for(int i=1;i<=v;i++){
 99         for(int j=1;j<i;j++){
100             Insert(i,j);
101         }
102     }
103 }
104 
105 inline void Insert(int a,int b){
106     top->from=a;
107     top->to=b;
108     top->flow=flow[a][b];
109     top->next=head[a];
110     head[a]=top;
111     top->rev=top+1;
112     top++;
113     top->from=b;
114     top->to=a;
115     top->flow=flow[b][a];
116     top->next=head[b];
117     head[b]=top;
118     top->rev=top-1;
119     top++;
120 }