diff --git a/S2OJ/104/104.cpp b/S2OJ/104/104.cpp new file mode 100644 index 00000000..9359bc93 --- /dev/null +++ b/S2OJ/104/104.cpp @@ -0,0 +1,98 @@ +#include +#include +#include +#include + +using std::cin; +using std::cout; +const char endl = '\n'; + +const int N = 405, + M = 15005, + INF = 0x3f3f3f3f; + +int n, m, s, t, flow, cost; + +// Graph +int idx, head[N], ver[M << 1], next[M << 1]; +std::pair edge[M << 1]; +// < c, w> + +void add(int u, int v, int c, int w) { + next[idx] = head[u]; + ver[idx] = v; + edge[idx] = std::make_pair(c, w); + head[u] = idx++; +} + +// Dinic +int dist[N]; +bool vis[N]; + +bool spfa() { + memset(vis, 0x00, sizeof(vis)); + memset(dist, 0x3f, sizeof(dist)); + std::queue q; + q.push(s); + dist[s] = 0; + vis[s] = true; + while (!q.empty()) { + int u = q.front(); + q.pop(); + vis[u] = false; + for (int i = head[u]; ~i; i = next[i]) { + int v = ver[i], + c = edge[i].first, + w = edge[i].second; + if (c > 0 && dist[v] > dist[u] + w) { + dist[v] = dist[u] + w; + if (!vis[v]) { + q.push(v); + vis[v] = true; + } + } + } + } + return dist[t] != INF; +} + +int dinic(int u, int limit) { + if (u == t) return limit; + + int flow = 0; + vis[u] = true; + for (int i = head[u]; ~i && flow < limit; i = next[i]) { + int v = ver[i], + c = edge[i].first, + w = edge[i].second; + if (dist[v] == dist[u] + w && c && !vis[v]) { + int k = dinic(v, std::min(c, limit - flow)); + if (!k) dist[v] = INF; + edge[i].first -= k; + edge[i ^ 1].first += k; + flow += k; + cost += k * w; + } + } + vis[u] = false; + return flow; +} + +int main() { + std::ios::sync_with_stdio(false); + memset(head, 0xff, sizeof(head)); + cin >> n >> m; + s = 1, t = n; + for (int i = 1; i <= m; i++) { + int u, v, c, w; + cin >> u >> v >> c >> w; + add(u, v, c, w); + add(v, u, 0, -w); + } + + while (spfa()) { + flow += dinic(s, INF); + } + cout << flow << ' ' << cost << endl; + return 0; +}