/in/foo.cc: In function 'bool search_(char*, int)':
/in/foo.cc:4:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j=i+1;j<strlen(a);j++)
                ~^~~~~~~~~~
/in/foo.cc: In function 'bool dbs(char*)':
/in/foo.cc:11:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(i!=strlen(a)){
        ~^~~~~~~~~~~