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#include <cstdio>
#include <cstring>
#define INF 1000000000
#define NIL -1
#define MAXN 1000
#define MAXM 5000
int c[2*MAXM+1], f[2*MAXM+1], from[MAXN+1], n, q[MAXN+1], h, val[2*MAXM+1], next[2*MAXM+1], lista[MAXN+1], e[MAXN+1];
inline void adauga(int x, int y, int z){
h++;
c[h]=z;
f[h]=0;
val[h]=y;
next[h]=lista[x];
lista[x]=h;
}
inline bool bfs(){
int st, dr, p;
st=0;
dr=1;
q[0]=1;
for(p=1; p<=n; p++){
from[p]=NIL;
}
memset(e, 0, sizeof e);
while((st<dr)&&(from[n]==NIL)){
for(p=lista[q[st]]; p; p=next[p]){
if((from[val[p]]==NIL)&&(c[p]>f[p])){
from[val[p]]=q[st];
e[val[p]]=p;
q[dr++]=val[p];
}
}
st++;
}
return (from[n]!=NIL);
}
int main(){
int m, i, x, y, z, ans, min, p, q;
FILE *fin, *fout;
fin=fopen("maxflow.in", "r");
fout=fopen("maxflow.out", "w");
fscanf(fin, "%d%d", &n, &m);
for(i=1; i<=m; i++){
fscanf(fin, "%d%d%d", &x, &y, &z);
adauga(x, y, z);
adauga(y, x, 0);
}
ans=0;
while(bfs()){
for(p=lista[n]; p; p=next[p]){
if(p%2==0){
q=p-1;
}else{
q=p+1;
}
if((from[val[p]]!=NIL)&&(c[q]>f[q])){
min=c[q]-f[q];
i=val[p];
while(i!=1){
if(min>c[e[i]]-f[e[i]]){
min=c[e[i]]-f[e[i]];
}
i=from[i];
}
f[q]+=min;
f[p]-=min;
i=val[p];
while(i!=1){
f[e[i]]+=min;
if(e[i]%2==0){
f[e[i]-1]-=min;
}else{
f[e[i]+1]-=min;
}
i=from[i];
}
ans+=min;
}
}
}
fprintf(fout, "%d\n", ans);
fclose(fin);
fclose(fout);
return 0;
}