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#include <iostream>
#include <cstring>
#include <queue>
#include <fstream>
const int MAXN = 1024;
const long long INF = 1e9;
struct edge {
int from, to, capacity, last;
};
int last[MAXN], level[MAXN];
edge edges[5 * MAXN];
long long dfs(int s, int t, int currcap, int copylast[])
{
if(s == t)
{
return currcap;
}
if(copylast[s] == -1)
{
return 0;
}
int ans = 0, ind = copylast[s];
auto edg = edges[copylast[s]];
bool is = false;
while(true)
{
if(level[edg.to] == level[edg.from] + 1)
{
int currv = dfs(edg.to, t, std::min(currcap, edg.capacity), copylast);
if(currv != 0)
{
is = true;
ans += currv;
edges[ind].capacity -= currv;
edges[ind ^ 1].capacity += currv;
}
}
if(!is)
{
copylast[edg.from] = edg.last;
}
if(edg.last == -1)
{
break;
}
ind = edg.last;
edg = edges[edg.last];
}
return ans;
}
long long bfs(int s, int t)
{
memset(level, -1, sizeof(level));
std::queue<int> k;
int copylast[MAXN];
for(int i = 0; i < MAXN; ++ i)
{
copylast[i] = last[i];
}
k.push(s);
level[s] = 0;
while(!k.empty())
{
int curr = k.front();
k.pop();
if(curr == t)
{
break;
}
auto edg = edges[last[curr]];
while(true)
{
if(edg.capacity != 0)
{
if(level[edg.to] == -1)
{
k.push(edg.to);
level[edg.to] = level[edg.from] + 1;
}
}
if(edg.last == -1)
{
break;
}
edg = edges[edg.last];
}
}
return dfs(s, t, INF, copylast);
}
int main()
{
#define cout myfileOut
std::ofstream myfileOut;
myfileOut.open ("maxflow.out");
#define cin myFileIn
std::ifstream myFileIn;
myFileIn.open ("maxflow.in");
memset(last, -1, sizeof(last));
int n, m;
cin >> n >> m;
for(int i = 0; i < m; ++ i)
{
int u, v, c;
cin >> u >> v >> c;
edges[i * 2] = {u, v, c, last[u]};
last[u] = i * 2;
edges[i * 2 + 1] = {v, u, 0, last[v]};
last[v] = i * 2 + 1;
}
long long ans = 0;
while(true)
{
long long curr = bfs(1, n);
if(curr)
{
ans += curr;
}else
{
cout << ans << '\n';
return 0;
}
}
return 0;
}