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#include <fstream>
#include <bits/stdc++.h>
using namespace std;
class InParser {
private:
FILE *fin;
char *buff;
int sp;
char read_ch() {
++sp;
if (sp == 4096) {
sp = 0;
fread(buff, 1, 4096, fin);
}
return buff[sp];
}
public:
InParser(const char* nume) {
fin = fopen(nume, "r");
buff = new char[4096]();
sp = 4095;
}
InParser& operator >> (int &n) {
char c;
while (!isdigit(c = read_ch()) && c != '-');
int sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
InParser& operator >> (long long &n) {
char c;
n = 0;
while (!isdigit(c = read_ch()) && c != '-');
long long sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
};
InParser f("maxflow.in");
ofstream g("maxflow.out");
vector<long long> G[2001];
long long n,m,i,x,y,z,flow,TT[2001],F[2001][2001],C[2001][2001],viz[2001],cd[2001],rasp,flowmin,nod;
long long BF()
{
int i, j, nod, V;
cd[0]=1;
cd[1]=1;
memset(viz,0,sizeof(viz));
viz[1]=1;
for (i=1; i<=cd[0]; i++)
{
nod=cd[i];
if(nod==n)
{
continue;
}
for(j=0; j<G[nod].size(); j++)
{
V=G[nod][j];
if(C[nod][V]==F[nod][V]||viz[V])
{
continue;
}
viz[V]=1;
cd[++cd[0]]=V;
TT[V]=nod;
}
}
return viz[n];
}
int main()
{
f>>n>>m;
for (i=1; i<=m; i++)
{
f>>x>>y>>z;
C[x][y]+=z;
G[x].push_back(y);
G[y].push_back(x);
}
for (flow=0; BF();)
{
for (i=0;i<G[n].size();i++)
{
nod=G[n][i];
if (F[nod][n]==C[nod][n]||!viz[nod])
{
continue;
}
TT[n]=nod;
flowmin=100000000009;
for(nod=n;nod!=1;nod=TT[nod])
{
flowmin=min(flowmin,C[TT[nod]][nod]-F[TT[nod]][nod]);
}
if(flowmin==0)
{
continue;
}
for(nod=n;nod!=1; nod=TT[nod])
{
F[TT[nod]][nod]+=flowmin;
F[nod][TT[nod]]-=flowmin;
}
flow+=flowmin;
}
}
g<<flow;
return 0;
}