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#include <fstream>
#include <iostream>
#include <climits>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
struct edge{
int capacity, flow;
};
int n, m, x, y, c;
edge matrix[1005][1005];
queue<int> q;
int father[1005];
int dist[1005];
vector<int> path;
vector<vector<int>> ad(1005);
int source, destination;
int bfs() {
for(int i = 1; i <= n; i++) {
dist[i] = INT_MAX;
father[i] = 0;
}
dist[source] = 0;
q.push(source);
while(!q.empty()) {
int node = q.front();
q.pop();
for(auto i : ad[node]) {
if(matrix[node][i].flow < matrix[node][i].capacity && dist[i] > dist[node] + 1) {
dist[i] = dist[node] + 1;
q.push(i);
father[i] = node;
}
}
}
if(dist[destination] == INT_MAX)
return 0; // destination can't be reached!
else
return 1; // destination reached!
}
int main() {
fin >> n >> m;
for (int i = 1; i <= m; i++ )
{
fin >> x >> y >> c;
matrix[x][y].capacity = c;
ad[x].push_back(y);
ad[y].push_back(x);
}
source = 1;
destination = n;
while(bfs()) {
path.clear();
int node = destination;
int min_flow = INT_MAX;
// calculate the maximal flow that can be pushed through this path
while(father[node] != 0) {
min_flow = min(min_flow, matrix[father[node]][node].capacity - matrix[father[node]][node].flow);
path.push_back(node);
node = father[node];
}
path.push_back(node);
// pushing the flow
reverse(path.begin(), path.end());
for(int i = 0; i < path.size() - 1; i ++) {
matrix[path[i]][path[i + 1]].flow += min_flow;
matrix[path[i + 1]][path[i]].flow -= min_flow;
}
}
int max_flow = 0;
for(int i = 1; i <= n; i++) {
max_flow += matrix[source][i].flow;
}
fout<< max_flow;
return 0;
}