/in/foo.cc: In function 'void dfs(int, int)':
/in/foo.cc:9:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(x==strlen(s)+1&&q==k)
     ~^~~~~~~~~~~~~
/in/foo.cc:15:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  else if(x==strlen(s)+1)
          ~^~~~~~~~~~~~~
/in/foo.cc:21:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<strlen(s);i++)
               ~^~~~~~~~~~
/in/foo.cc:27:12: error: too few arguments to function 'void dfs(int, int)'
     dfs(x+1);
            ^
/in/foo.cc:7:6: note: declared here
 void dfs(int x,int k)
      ^~~