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#include <cstdio>
#include <vector>
#include <algorithm>
#include <bitset>
#include <queue>
#define Nmax 1005
#define INF 0x3f3f3f3f
#define v first
#define e second
using namespace std;
class edge{
public:
int x,y,capacity,flow;
edge(){
x = y = capacity = flow = 0;
}
edge(int a,int b,int c,int f){
this->x = a;
this->y = b;
this->capacity = c;
this->flow = f;
}
};
queue<int> Q;
bitset<Nmax> used;
vector<edge>E;
vector<pair<int,int> > G[Nmax];
int N,M,nr = -1;
int daddy[Nmax];
void Insert(int from,int to,int cp,int fl){
++nr;
E.push_back(edge(from,to,cp,fl));
G[from].push_back(make_pair(to,nr));
}
void Read()
{
scanf("%d%d",&N,&M);
int a,b,c;
for(int i = 1; i <= M; ++i)
{
scanf("%d%d%d",&a,&b,&c);
Insert(a,b,c,0);
Insert(b,a,0,0);
}
}
bool BFS(int k)
{
used = 0;
Q.push(k);
used[k] = 1;
while(!Q.empty())
{
k = Q.front(); Q.pop();
if(k == N) continue;
for(vector<pair<int,int> >::iterator it = G[k].begin(); it != G[k].end(); ++it)
if(!used[it->v] && E[it->e].capacity - E[it->e].flow != 0)
{
Q.push(it->v);
daddy[it->v] = it->e;
used[it->v] = 1;
}
}
return used[N];
}
void FLOW(int k)
{
int maxFLOW = 0,minFLOW;
while(BFS(k))
for(vector<pair<int,int> >::iterator it = G[N].begin(); it != G[N].end(); ++it)
{
if(E[it->e^1].capacity == E[it->e^1].flow)
continue;
daddy[N] = it->e^1;
minFLOW = INF;
for(int nodc = N; nodc != 1; nodc = E[daddy[nodc]].x)
minFLOW = min(minFLOW,E[daddy[nodc]].capacity - E[daddy[nodc]].flow);
if(minFLOW == 0)
continue;
for(int nodc = N; nodc != 1; nodc = E[daddy[nodc]].x)
{
E[daddy[nodc]].flow += minFLOW;
E[daddy[nodc]^1].flow -= minFLOW;
}
maxFLOW += minFLOW;
}
printf("%d\n",maxFLOW);
}
int main()
{
freopen("maxflow.in","r",stdin);
freopen("maxflow.out","w",stdout);
Read();
FLOW(1);
return 0;
}