/in/foo.cc: In function 'int DFS(int, int)':
/in/foo.cc:51:54: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
    if (flow = DFS(i, min(low, e[v][i].w - e[v][i].f))){
                                                      ^
/in/foo.cc: In function 'int dinic()':
/in/foo.cc:64:27: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   while (flow = DFS(s, INF)){
                           ^