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///edmons karp
#include<fstream>
#include<vector>
#define inf 1e9
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
int const N = 1003;
int n , m , a , b;
int f[N][N];
int q[N] , t[N] , lv[N] , fl[N];
vector<int> v[N];
inline bool bfs(){
for(int i = 1 ; i <= n ; ++ i)
lv[i] = inf;
int l = 1 , r = 1;
q[1] = 1 , lv[1] = 0;
fl[n] = fl[1] = inf;
while(l <= r){
int x = q[l++];
for(int i : v[x]){
if(f[x][i] > 0 && lv[i] == inf){
lv[i] = 1 + lv[x];
fl[i] = (fl[x] < f[x][i] ? fl[x] : f[x][i]);
t[i] = x;
q[++r] = i;
}
}
}
return lv[n] < inf;
}
int maxflow(){
int flow = 0;
while(bfs()){
flow += fl[n];
int x = n;
while(t[x]){
f[t[x]][x] -= fl[n];
f[x][t[x]] += fl[n];
x = t[x];
}
}
return flow;
}
int main(){
fin >> n >> m;
for(int i = 1 ; i <= m ; ++ i){
fin >> a >> b >> f[a][b];
v[a].push_back(b);
v[b].push_back(a);
}
fout << maxflow() << '\n';
return 0;
}