二分图

include

include

include

using namespace std;
const int N = 510, M = 100010;
int n1, n2, m;
int h[N], e[M], ne[M], idx;
int match[N];
bool st[N];

void add(int a, int b) {
e[idx] = b, ne[idx] = h[a], h[a] = idx++;
}

bool find(int x) {
for (int i = h[x]; i != -1; i = ne[i]) {
int j = e[i];
if (!st[j]) {
st[j] = true;
if (match[j] == 0 || find(match[j])) {
match[j] = x;
return true;
}
}
}
return false;
}

int main() {
cin >> n1 >> n2 >> m;
memset(h, -1, sizeof h);

while (m--) {
    int a, b;
    cin >> a >> b;
    add(a, b);
}

int res = 0;
for (int i = 1; i <= n1; ++i) {
    memset(st, false, sizeof st);
    if (find(i)) res++;
}

cout << res << endl;
return 0;

}

原文地址:https://www.cnblogs.com/clown9804/p/12541943.html