Fix bipartite_match

Signed-off-by: Bruno Freitas Tissei <bft15@inf.ufpr.br>

algorithms/graph/bipartite_match.cpp

 /**
  * Bipartite Matching
  *
- * Complexity (Time): O(V + E)
- * Complexity (Space): O(V + E)
+ * Complexity (Time): O(V*E)
+ * Complexity (Space): O(V*E)
  */
 
 vector<int> graph[MAX];
@@ -15,7 +15,7 @@ int dfs(int x) {
 
   cont[x] = 1;
   for (auto i : graph[x])
-    if (match[i] == -1 || dfs(match[v])) {
+    if (match[i] == -1 || dfs(match[i])) {
       match[i] = x;
       return 1;
     }