View Compilation Error

0_0_24902568_29798.cpp: In function 'int dfs(int, int, int)':
0_0_24902568_29798.cpp:95:20: error: 's' was not declared in this scope
     for(int i=head[s];~i;i=edge[i].next)
                    ^
0_0_24902568_29798.cpp:97:6: error: 'e' was not declared in this scope
      e=edge[i];int v=edge[i].to;
      ^