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#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
struct flow {
struct edge {
int to;
int cap;
int spre;
};
const int INF = (int) 1e9;
int n;
vector<int> head;
vector<edge> edges;
vector<int> level;
vector<int> pt;
void init(int nn) {
n = nn;
edges.clear();
head.resize(n + 1, -1);
pt.resize(n + 1);
level.resize(n + 1);
}
void add(int a, int b, int c, int d = 0) {
edges.push_back({b, c, head[a]});
edges.push_back({a, d, head[b]});
head[a] = (int) edges.size() - 2;
head[b] = (int) edges.size() - 1;
}
int dfs(int a, int cap) {
if (cap == 0 || a == n) {
return cap;
}
while (pt[a] != -1) {
int i = pt[a];
if (edges[i].cap && level[edges[i].to] == 1 + level[a]) {
int b = edges[i].to;
int x = dfs(b, min(cap, edges[i].cap));
if (x > 0) {
edges[i].cap -= x;
edges[i ^ 1].cap += x;
return x;
}
}
pt[a] = edges[pt[a]].spre;
}
return 0;
}
int get() {
int ret = 0;
while (1) {
for (int i = 1; i <= n; i++) {
level[i] = -1;
pt[i] = 0;
}
level[1] = 0;
queue<int> q;
q.push(1);
while (!q.empty()) {
int a = q.front();
q.pop();
int ind = head[a];
while (ind != -1) {
if (edges[ind].cap > 0) {
int b = edges[ind].to;
if (level[b] == -1) {
level[b] = 1 + level[a];
q.push(b);
}
}
ind = edges[ind].spre;
}
}
if (level[n] == -1) {
break;
}
pt = head;
while (1) {
int x = dfs(1, INF);
if (x == 0) {
break;
}
ret += x;
}
}
return ret;
}
};
int main() {
freopen ("maxflow.in", "r", stdin);
freopen ("maxflow.out", "w", stdout);
int n, m;
scanf("%d %d", &n, &m);
flow f;
f.init(n);
for (int i = 1; i <= m; i++) {
int x, y, z;
scanf("%d %d %d", &x, &y, &z);
f.add(x, y, z);
}
printf("%d\n", f.get());
}