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#include <fstream>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;
using VI = vector<int>;
using VB = vector<bool>;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
const int Inf = 0x3f3f3f3f, MaxN = 1005;
int n, m;
vector<VI> G, C;
queue<int> Q;
VI t;
VB v;
void Read();
int MaxFlow(int source, int sink);
bool Bf(int source, int sink);
int main()
{
Read();
fout << MaxFlow(1, n);
fin.close();
fout.close();
}
int MaxFlow(int source, int sink)
{
int maxflow = 0, fmin;
while ( Bf(source, sink) )
for (const int& x : G[sink])
{
if (!v[x] || C[x][sink] <= 0)
continue;
t[sink] = x;
fmin = Inf;
for (int i = sink; i != source; i = t[i])
fmin = min(fmin, C[t[i]][i]);
if (!fmin)
continue;
for (int i = sink; i != source; i = t[i])
{
C[t[i]][i] -= fmin;
C[i][t[i]] += fmin;
}
maxflow += fmin;
}
return maxflow;
}
bool Bf(int source, int sink)
{
v = VB(n + 1);
t = VI(n + 1);
v[source] = true;
Q.push(source);
int x;
while (!Q.empty())
{
x = Q.front();
Q.pop();
if (x == sink)
continue;
for (const int& y : G[x])
if (!v[y] && C[x][y] > 0)
{
v[y] = true;
t[y] = x;
Q.push(y);
}
}
return v[sink];
}
void Read()
{
fin >> n >> m;
G = vector<VI>(n + 1);
C = vector<VI>(n + 1, VI(n + 1));
t = VI(n + 1);
int x, y, c;
for (int i = 1; i <= m; i++)
{
fin >> x >> y >> c;
G[x].push_back(y);
G[y].push_back(x);
C[x][y] += c;
}
}