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#include <fstream>
#include <queue>
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
const int NMAX = 1e3 + 1;
int N, M;
vector < int > G[NMAX];
int C[NMAX][NMAX];
int F[NMAX][NMAX];
bool Sel[NMAX];
int T[NMAX];
static inline void Add_Edge (int x, int y, int z)
{
G[x].push_back(y), G[y].push_back(x);
C[x][y] = z;
return;
}
static inline void Read ()
{
f.tie(nullptr);
f >> N >> M;
for(int i = 1; i <= M; ++i)
{
int x = 0, y = 0, z = 0;
f >> x >> y >> z;
Add_Edge(x, y, z);
}
return;
}
static inline void Reset ()
{
for(int i = 1; i <= N; ++i)
Sel[i] = 0, T[i] = -1;
return;
}
static inline bool BFS (int S, int D)
{
Reset();
queue < int > Q;
Q.push(S), Sel[S] = 1, T[S] = 0;
while(!Q.empty())
{
int Node = Q.front();
Q.pop();
for(auto it : G[Node])
if(!Sel[it] && F[Node][it] < C[Node][it])
{
Sel[it] = 1, T[it] = Node;
if(it == D)
return 1;
Q.push(it);
}
}
return 0;
}
static inline int my_min (int a, int b)
{
return ((a < b) ? a : b);
}
static inline int MaxFlow (int S, int D)
{
int flow = 0;
while(BFS(S, D))
{
for(auto it : G[D])
if(T[it] != -1)
{
int Node = it;
int Min = C[Node][D] - F[Node][D];
while(Node != S)
{
int Dad = T[Node];
Min = my_min(Min, C[Dad][Node] - F[Dad][Node]);
Node = Dad;
}
///
flow += Min;
///
Node = it;
F[Node][D] += Min;
/// F[D][Node] -= Min;
while(Node != S)
{
int Dad = T[Node];
F[Dad][Node] += Min;
/// F[Node][Dad] -= Min;
Node = Dad;
}
}
}
return flow;
}
int main()
{
Read();
g << MaxFlow(1, N) << '\n';
return 0;
}