#include <fstream>
#include <vector>
#include <queue>
#include <climits>

using namespace std;

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

struct Muchie {
    int nod, flow, cp, rev;
};

int n, m, x, y, z;
vector<Muchie> G[1005];
int level[1005];

bool bfs(int s, int d) {
    for(int i = 1; i <= n; i++) {
        level[i] = -1;
    }
    level[s] = 0;
    queue<int> Q;
    Q.push(s);
    while(!Q.empty()) {
        int nod = Q.front();
        Q.pop();
        for(auto i : G[nod]) {
            int vecin = i.nod, cp = i.cp, flow = i.flow;
            if(level[vecin] < 0 && flow < cp) {
                level[vecin] = level[nod] + 1;
                Q.push(vecin);
            }
        }
    }
    return level[d] >= 0;
}

int getFlow(int s, int d, int flow, int st[]) {
    if(s == d) {
        return flow;
    }
    for(; st[s] < G[s].size(); st[s]++) {
        Muchie& m = G[s][st[s]];
        int vecin = m.nod, flowVecin = m.flow, cp = m.cp;
        if(level[vecin] == level[s] + 1 && flowVecin < cp) {
            int flowCurent = min(flow, cp - flowVecin);
            int temp = getFlow(vecin, d, flowCurent, st);
            if(temp > 0) {
                m.flow += temp;
                G[vecin][m.rev].flow -= temp;
                return temp;
            }
        }
    }
    return 0;
}

int dinic(int s, int d) {
    if(s == d) {
        return -1;
    }
    int total = 0;
    while(bfs(s, d)) {
        int *start = new int[n + 1]{0};
        while(int flow = getFlow(s, d, INT_MAX, start)) {
            total += flow;
        }
    }
    return total;
}

int main() {
    fin >> n >> m;
    for(int i = 1; i <= m; i++) {
        fin >> x >> y >> z;
        G[x].push_back({y, 0, z, (int) G[y].size()});
        G[y].push_back({x, 0, 0, (int) G[x].size()});
    }
    fout << dinic(1, n);
    return 0;
}