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#include <bits/stdc++.h>
#define INF 0x3f3f3f3f
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
/**
int n,m,viz[1001],s,d;
int f[1001][1001],c[1001][1001];
int q[1001];
int bfs()
{
int p,u,i,x;
q[0]=s;
p=u=0;
viz[s]=1;
while(p<=u&&!viz[d])
{
x=q[p++];
for(int i=1;i<=n;i++)
if(!viz[i])
if(f[x][i]<c[x][i]) {viz[i]=x; q[++u]=i;}
else
if(f[i][x]>0) {viz[i]=-x; q[++u]=i;}
}
return !viz[d];
}
void damfluxlapompa()
{
int i,a,b,lg,v;
int l[101];
do
{
memset(viz,0,sizeof(viz));
if(bfs()) return ;
l[0]=d;lg=0;
a=b=INF;
while(l[lg]!=s)
{
++lg;
l[lg]=abs(viz[l[lg-1]]);
if(viz[l[lg-1]]>0) a=min(a,c[l[lg]][l[lg-1]]-f[l[lg]][l[lg-1]]);
else
if(viz[l[lg-1]]<0) b=min(b,f[l[lg-1]][l[lg]]);
}
v=min(a,b);
for(int i=lg;i>0;i--)
if(viz[l[i-1]]>0)
f[l[i]][l[i-1]]+=v;
else
f[l[i-1]][l[i]]-=v;
}while(1);
}
int main()
{
f1>>n>>m;
s=1; d=n;
for(int i=1;i<=m;i++)
{
int x,y,flux;
f1>>x>>y>>flux;
c[x][y]=flux;
}
damfluxlapompa();
int sum=0;
for(int i=1;i<=n;i++)
sum+=f[i][d];
g<<sum<<'\n';
return 0;
}
**/
int n,m,s,d;
vector<int> v[1001];
int flux,c[1001][1001],t[1001];
queue<int> q;
int bf()
{
memset(t,0,sizeof(t));
t[1]=1;
q.push(s);
while(q.size())
{
int i=q.front();
q.pop();
for(auto j: v[i])
{
if(t[j]==0&&c[i][j]>0)
{
t[j]=i;
if(j!=d) q.push(j);
}
}
}
if(t[d]) return 1;
return 0;
}
int flux_maxim()
{
while(bf())
{
for(auto i: v[d])
if(t[i])
{
t[d]=i;
int minn=2000000000;
i=d;
while(i!=s)
{
minn=min(minn,c[t[i]][i]);
i=t[i];
}
i=d;
while(i!=s)
{
c[t[i]][i]-=minn;
c[i][t[i]]+=minn;
i=t[i];
}
flux+=minn;
}
}
return flux;
}
int main()
{
f>>n>>m;
for(int i=1;i<=m;i++)
{
int x,y,ci;
f>>x>>y>>ci;
v[x].push_back(y);
v[y].push_back(x);
c[x][y]=ci;
}
s=1; d=n;
g<<flux_maxim()<<'\n';
return 0;
}