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#include<stdio.h>
#include<cstring>
#include<queue>
#include<vector>
using namespace std;
#define MAX_N 1000
#define mp make_pair
#define pb push_back
int n, m;
int graph[MAX_N][MAX_N];
vector<int> list[MAX_N];
void read(FILE *fin){
fscanf(fin, "%d%d", &n, &m);
int a, b, c;
for(int i=1; i<=m; i++){
fscanf(fin, "%d%d%d", &a, &b, &c);
graph[a][b] = c;
list[a].push_back(b);
}
}
int father[MAX_N]; // vector de tati folosit in parcurgerea bf;
int st[MAX_N]; // vector in care adaug pe rand nodurile in parcurgerea bf
int v_min[MAX_N];
bool bf(int s, int t){ // s - pct de plecare, t-pct destinatie
bool viz[MAX_N];
for(int i=1; i<=n; i++) viz[i] = false;
father[s] = -1; // sursa nu are tata;
viz[s] = true;
int p=1, q=1;
st[q] = s;
while(p <= q){
int nod = st[p];
if (nod == t) return 1;
for(size_t i=0; i<list[nod].size(); i++){
int next = list[nod][i];
if(!viz[next] && graph[nod][next]){
viz[next] = true;
father[next] = nod;
q++; st[q] = next;
v_min[next] = graph[nod][next];
if(v_min[nod]!=0)
if(v_min[next] > v_min[nod]) v_min[next] = v_min[nod];
}
}
p++;
}
return viz[t] == true;
} // functia returneaza true daca exista drum de la s la t;
int solve(int s, int t){
int max_flow = 0;
while(bf(s,t)){ // cat timp exista drum de la s la t;
int minim = v_min[t];
for(int i=t; i!=s; i=father[i]){
if(graph[i][father[i]] == 0) list[i].push_back(father[i]);
graph[i][father[i]] += minim;
graph[father[i]][i] -= minim;
}
max_flow +=minim;
}
return max_flow;
}
int main(){
FILE *fin = fopen("maxflow.in", "rt");
FILE *fout = fopen("maxflow.out", "wt");
read(fin);
fprintf(fout, "%d\n", solve(1, n));
return 0;
}