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#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
int n,m,ans;
const int N=1e3+5;
vector<int>a[N];
bool viz[N];
int nr[N],tt[N],niv[N];
int d[N][N];
void bfs()
{
for(int i=1;i<=n;i++)
{
viz[i]=0;
niv[i]=-1;
}
niv[1]=0;
queue<int>q;
q.push(1);
while(!q.empty())
{
int nod=q.front();
q.pop();
for(auto x: a[nod])
if(niv[x]==-1&&d[nod][x]>0)
{
niv[x]=niv[nod]+1;
q.push(x);
if(x==n)
return;
}
}
}
int dfs(int nod,int mn)
{
if(mn==0||nod==n)
return mn;
for(auto x:a[nod])
if(d[nod][x]>0&&niv[x]==niv[nod]+1)
{
int R=dfs(x,min(mn,d[nod][x]));
if(R>0)
{
d[nod][x]-=R;
d[x][nod]+=R;
return R;
}
}
return 0;
}
bool flux()
{
bfs();
if(niv[n]==-1)
return 0;
int val=0;
while(true)
{
int x=dfs(1,1e9);
if(x==0)
break;
val+=x;
}
ans+=val;
if(val!=0)
return 1;
return false;
}
int main()
{
f>>n>>m;
int x,y,z;
for(int i=1;i<=m;i++)
{
f>>x>>y>>z;
a[x].push_back(y);
a[y].push_back(x);
d[x][y]=z;
}
while(flux());
g<<ans;
return 0;
}