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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))
#define pb(a) push_back(a)
//#pragma GCC optimize("O3")
using namespace std;
using namespace __gnu_pbds;
auto random_address = [] { char *p = new char; delete p; return uint64_t(p); };
const uint64_t SEED = chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1);
mt19937_64 rng(SEED);
typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
ll n,m,flux[1001][1001],inv[1001][1001],ans;
vector<pll> muchii[1001];
deque<pair<pll,ll>> path;
bool use[1001];
void dfs(int nod)
{
use[nod]=1;
if(nod==n||use[n])
return;
for(auto it:muchii[nod])
{
int i=it.first;
int c=it.second;
if(use[i])
continue;
if(c==0)
{
if(inv[nod][i]<c)
{
dfs(i);
if(use[n])
{
path.push_back({{nod,i},c});
break;
}
}
}
else
{
if(flux[nod][i]<c)
{
dfs(i);
if(use[n])
{
path.push_back({{nod,i},c});
break;
}
}
}
}
}
int main()
{
ios_base::sync_with_stdio(false);
fin.tie(0);
fout.tie(0);
fin>>n>>m;
for(int i=1;i<=m;i++)
{
int a,b,c;
fin>>a>>b>>c;
muchii[a].pb(make_pair(b,c));
muchii[b].pb(make_pair(a,0));
}
while(true)
{
path.clear();
memset(use,0,sizeof(use));
dfs(1);
if(use[n]==0)
break;
ll val=1e9;
for(auto i:path)
{
int dif,nod1=i.first.first,nod2=i.first.second,c=i.second;
if(c==0)
dif=c-inv[nod1][nod2];
else
dif=c-flux[nod1][nod2];
val=min(val,dif);
}
ans+=val;
if(val==1e9)
break;
for(auto i:path)
{
int nod1=i.first.first,nod2=i.first.second,c=i.second;
if(c==0)
{
inv[nod1][nod2]+=val;
flux[nod1][nod2]-=val;
}
else
{
flux[nod1][nod2]+=val;
inv[nod1][nod2]-=val;
}
}
}
fout<<ans;
return 0;
}