0
1
mirror of https://git.sb/baoshuo/OI-codes.git synced 2024-12-25 06:31:59 +00:00
OI-codes/S2OJ/340/340.cpp

122 lines
2.8 KiB
C++

#include <iostream>
#include <functional>
#include <queue>
#include <tuple>
#include <vector>
using std::cin;
using std::cout;
const char endl = '\n';
const int INF = 0x3f3f3f3f;
int main() {
std::ios::sync_with_stdio(false);
cin.tie(nullptr);
int t;
cin >> t;
while (t--) {
int n, m;
cin >> n >> m;
int s = 0, t = 1;
std::vector<int> a(n + 1), pre(n + 1), head((m + 1) << 1, -1);
std::vector<std::tuple<int, int, int>> edges;
for (int i = 1; i <= n; i++) {
cin >> a[i];
}
std::function<void(int, int, int)> add = [&](int u, int v, int w) -> void {
edges.emplace_back(v, w, head[u]);
head[u] = edges.size() - 1;
};
for (int i = 1, x, y; i <= m; i++) {
cin >> x >> y;
add(i << 1, i << 1 | 1, 1);
add(i << 1 | 1, i << 1, 1);
add(pre[x], i << 1, pre[x] ? a[x] : 1);
add(i << 1, pre[x], 0);
pre[x] = i << 1;
add(pre[y], i << 1 | 1, pre[y] ? a[y] : 1);
add(i << 1 | 1, pre[y], 0);
pre[y] = i << 1 | 1;
}
add(pre[1], t, a[1]);
add(t, pre[1], 0);
std::vector<int> dist((m + 1) << 1);
std::function<bool()> bfs = [&]() -> bool {
std::fill(dist.begin(), dist.end(), 0);
std::queue<int> q;
q.emplace(s);
dist[s] = 1;
while (!q.empty()) {
int u = q.front();
q.pop();
for (int i = head[u]; ~i; i = std::get<2>(edges[i])) {
int v = std::get<0>(edges[i]),
w = std::get<1>(edges[i]);
if (!dist[v] && w) {
dist[v] = dist[u] + 1;
if (v == t) return true;
q.emplace(v);
}
}
}
return false;
};
std::function<int(int, int)> dinic = [&](int u, int limit) -> int {
if (u == t) return limit;
int flow = 0;
for (int i = head[u]; ~i; i = std::get<2>(edges[i])) {
int v = std::get<0>(edges[i]),
w = std::get<1>(edges[i]);
if (dist[v] == dist[u] + 1 && w) {
int k = dinic(v, std::min(w, limit - flow));
if (!k) dist[v] = 0;
std::get<1>(edges[i]) -= k;
std::get<1>(edges[i ^ 1]) += k;
flow += k;
}
}
return flow;
};
int res = 0;
while (bfs()) {
while (int flow = dinic(s, INF)) res += flow;
}
cout << res << endl;
}
return 0;
}