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-rw-r--r--graph/hopcroftKarp.cpp47
1 files changed, 0 insertions, 47 deletions
diff --git a/graph/hopcroftKarp.cpp b/graph/hopcroftKarp.cpp
deleted file mode 100644
index c1f5d1c..0000000
--- a/graph/hopcroftKarp.cpp
+++ /dev/null
@@ -1,47 +0,0 @@
-vector<vector<int>> adj;
-// pairs ist der gematchte Knoten oder -1
-vector<int> pairs, dist, ptr;
-
-bool bfs(int l) {
- queue<int> q;
- for(int v = 0; v < l; v++) {
- if (pairs[v] < 0) {dist[v] = 0; q.push(v);}
- else dist[v] = -1;
- }
- bool exist = false;
- while(!q.empty()) {
- int v = q.front(); q.pop();
- for (int u : adj[v]) {
- if (pairs[u] < 0) {exist = true; continue;}
- if (dist[pairs[u]] < 0) {
- dist[pairs[u]] = dist[v] + 1;
- q.push(pairs[u]);
- }}}
- return exist;
-}
-
-bool dfs(int v) {
- for (; ptr[v] < sz(adj[v]); ptr[v]++) {
- int u = adj[v][ptr[v]];
- if (pairs[u] < 0 ||
- (dist[pairs[u]] > dist[v] && dfs(pairs[u]))) {
- pairs[u] = v; pairs[v] = u;
- return true;
- }}
- return false;
-}
-
-int hopcroft_karp(int l) { // l = #Knoten links
- int ans = 0;
- pairs.assign(sz(adj), -1);
- dist.resize(l);
- // Greedy Matching, optionale Beschleunigung.
- for (int v = 0; v < l; v++) for (int u : adj[v])
- if (pairs[u] < 0) {pairs[u] = v; pairs[v] = u; ans++; break;}
- while(bfs(l)) {
- ptr.assign(l, 0);
- for(int v = 0; v < l; v++) {
- if (pairs[v] < 0) ans += dfs(v);
- }}
- return ans;
-}