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#include <algorithm>
#include <iostream>
#include <fstream>
#include <climits>
#include <vector>
#include <queue>
using namespace std;
ifstream in("cuplaj.in");
ofstream out("cuplaj.out");
const int NMAX = 20000 + 5;
struct Edge{
int to;
int rev;
int flow;
};
int n, m, e;
int src, dest, tot;
int rem[1 + NMAX];
int dist[1 + NMAX];
bool connected[1 + NMAX];
vector < Edge > g[1 + NMAX];
void addedge(int i, int j){
Edge direct = {j, g[j].size(), 0};
Edge inverse = {i, g[i].size(), 0};
g[i].push_back(direct);
g[j].push_back(inverse);
}
void read(){
in >> n >> m >> e;
tot = n + m;
src = 0;
dest = tot + 1;
for(int i = 1; i <= n; i++)
addedge(src, i);
for(int i = n + 1; i <= tot; i++)
addedge(i, dest);
for(int i = 1; i <= e; i++){
int x, y;
in >> x >> y;
addedge(x, n + y);
}
}
bool bfs(){
fill(dist, dist + tot + 2, -1);
queue < int > q;
q.push(src);
dist[src] = 0;
while(!q.empty()){
int from = q.front();
q.pop();
for(int i = 0; i < g[from].size(); i++){
Edge &e = g[from][i];
int to = e.to;
if(dist[to] < 0 && e.flow < 1){
dist[to] = dist[from] + 1;
q.push(to);
}
}
}
return (0 <= dist[dest]);
}
int dfs(int from, int deltaflow){
if(from == dest)
return deltaflow;
else{
for(int i = rem[from]; i < g[from].size(); i++){
Edge &e = g[from][i];
if(dist[e.to] == dist[from] + 1){
int cap = (e.flow == 1) ? 0 : 1;
int addflow = dfs(e.to, min(deltaflow, cap));
if(0 < addflow){
e.flow += addflow;
g[e.to][e.rev].flow -= addflow;
rem[from] = i;
return addflow;
}
}
}
return 0;
}
}
int maxflow(){
int result = 0;
while(bfs()){
fill(rem, rem + tot + 2, 0);
while(int deltaflow = dfs(src, INT_MAX)){
result += deltaflow;
}
}
return result;
}
int main()
{
read();
out << maxflow() << '\n';
in.close();
out.close();
return 0;
}