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#include<fstream>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;


ifstream in("maxflow.in");
ofstream out("maxflow.out");

vector<int> G[1001];
int N, M, a, b, c, i, T = 0;
int viz[1001];
int from[1001], O[1001], A[1001][1001];
int BFS(int x)
{
	queue<int> q;
	q.push(x);
	viz[x] = T + 1;
	int i;
	while (q.size())
	{
		x = q.front();
		q.pop();
		for (i = 0; i < G[x].size();++i)
			if (viz[G[x][i]] <= T && A[x][G[x][i]]>0)
			{
				q.push(G[x][i]);
				viz[G[x][i]] = T + 1;
				from[G[x][i]] = x;
				if (G[x][i] == N)
				{
					return 1;
				}
			}
	}
	return 0;
}
void update(int x)
{
	int min_value = 1 << 30;
	int root = x;
	if (A[from[x]][x]==0)
		return;
	while (from[x])
	{
		min_value = min(min_value, A[from[x]][x]);
		x = from[x];
	}
	if (min_value == 0)
		return;
	x = root;
	while (from[x])
	{
		if (A[from[x]][x] - min_value >= 0)
		{
			A[from[x]][x] = A[from[x]][x] - min_value;
			A[x][from[x]] = A[x][from[x]] + min_value;
		}
		else
		{
			A[from[x]][x] = A[from[x]][x] + min_value;
			A[x][from[x]] = A[x][from[x]] - min_value;
		}
		x = from[x];
	}
}
void Edmond()
{
	while (BFS(1))
	{
		update(N);
		++T;
	}
}



int main()
{
	in >> N >> M;
	for (i = 1; i <= M; ++i)
	{
		in >> a >> b >> c;
		G[a].push_back(b);
		A[a][b] = c;
		G[b].push_back(a);
	}
	for (i = 0; i < G[1].size(); ++i)
		O[i] = A[1][G[1][i]];
	Edmond();
	int s = 0;
	for (i = 0; i < G[1].size(); ++i)
		s += O[i] - A[1][G[1][i]];
	out << s;
	return 0;
}