Merge pull request #63 from atcoder/patch/maxflow

nit picking optimization for maxflow

Author: yosupo06

atcoder/maxflow.hpp

@@ -99,8 +99,9 @@ template <class Cap> struct mf_graph {
                 g[v][i].cap += d;
                 g[e.to][e.rev].cap -= d;
                 res += d;
-                if (res == up) break;
+                if (res == up) return res;
             }
+            level[v] = _n;
             return res;
         };
 
@@ -109,11 +110,9 @@ template <class Cap> struct mf_graph {
             bfs();
             if (level[t] == -1) break;
             std::fill(iter.begin(), iter.end(), 0);
-            while (flow < flow_limit) {
-                Cap f = dfs(dfs, t, flow_limit - flow);
-                if (!f) break;
-                flow += f;
-            }
+            Cap f = dfs(dfs, t, flow_limit - flow);
+            if (!f) break;
+            flow += f;
         }
         return flow;
     }