View Compilation Error

0_0_38463822_24638.c: In function 'dfs':
0_0_38463822_24638.c:12:9: error: 'len' undeclared (first use in this function)
  if(now>len)
         ^
0_0_38463822_24638.c:12:9: note: each undeclared identifier is reported only once for each function it appears in
0_0_38463822_24638.c: In function 'main':
0_0_38463822_24638.c:58:13: error: expected expression before 'int'
     l=max(l,int(a[i][0]));
             ^