HDOJ1150(最小点集覆盖)

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

#define N 101

int match
;
bool vis
;
vector <int> e
;
int n, m, k;

void InitRead();

void DataProcess();

bool Dfs(int x);

int main()
{
while (~scanf("%d", &n))
{
if (n == 0) break;
InitRead();
DataProcess();
}
return 0;
}

void InitRead()
{
scanf("%d %d", &m, &k);
memset(match, -1, sizeof(match));
for (int i=0; i<N; ++i) e[i].clear();
int a, b;
for (int i=0; i<k; ++i)
{
scanf("%*d %d %d", &a, &b);
if (a == 0 || b == 0) continue;     //可以用模式0解决的任务不建边
e[a].push_back(b);
}
return;
}

void DataProcess()
{
int ans = 0;
for (int i=0; i<n; ++i)
{
memset(vis, false, sizeof(vis));
if (Dfs(i)) ans++;
}
printf("%d\n", ans);
return;
}

bool Dfs(int x)
{
int size = e[x].size();
for (int i=0; i<size; ++i)
{
if (!vis[e[x][i]])
{
vis[e[x][i]] = true;
if (match[e[x][i]] == -1 || Dfs(match[e[x][i]]))
{
match[e[x][i]] = x;
return true;
}
}
}
return false;
}