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#include <fstream>
#include <vector>
#include <iostream>
#include <stack>
#define MAXN 10001
#define MAXINT 1000000000
using namespace std;
vector<int> flow[MAXN][2];
stack<int> q;
int pred[MAXN];
inline void reset(){
q = stack<int>();
for(int i = 0; i < MAXN; i++){
pred[i] = -1;
}
}
int edmonds_karp(int s, int t) {
q.push(s);
while(!q.empty()){
int u = q.top();
q.pop();
for(int i = 0; i < flow[u][0].size(); i++){
int v = flow[u][0][i];
int c = flow[u][1][i];
if(c > 0 && pred[v] == -1){
pred[v] = u;
q.push(v);
}
}
}
if(pred[t] == -1){
return 0;
}
int min = MAXINT;
int v = t;
while(v != s){
int u = pred[v];
for(int i = 0; i < flow[u][0].size(); i++){
if(flow[u][0][i] == v){
if(flow[u][1][i] < min){
min = flow[u][1][i];
}
break;
}
}
v = u;
}
v = t;
while(v != s){
int u = pred[v];
for(int i = 0; i < flow[u][0].size(); i++){
if(flow[u][0][i] == v){
flow[u][1][i] -= min;
break;
}
}
for(int i = 0; i < flow[v][0].size(); i++){
if(flow[v][0][i] == u){
flow[v][1][i] += min;
break;
}
}
v = u;
}
return min;
}
int main()
{
int n, m;
ifstream inFile;
ofstream outFile;
inFile.open("maxflow.in");
outFile.open("maxflow.out");
inFile >> n >> m;
for (int i = 0; i < m; i++)
{
int a, b, c;
inFile >> a >> b >> c;
flow[a][0].push_back(b);
flow[a][1].push_back(c);
flow[b][0].push_back(a);
flow[b][1].push_back(0);
}
int maxFlow = 0;
while(true){
reset();
int f = edmonds_karp(1, n);
if(f == 0){
break;
}
else{
maxFlow += f;
}
}
outFile << maxFlow << endl;
inFile.close();
outFile.close();
return 0;
}