/in/foo.cc: In function 'char* quling(char*, char*)':
/in/foo.cc:14:8: warning: statement has no effect [-Wunused-value]
   for(s;s<v;s++){
        ^
/in/foo.cc: In function 'int cmp(char*, char*, char*, char*)':
/in/foo.cc:36:10: warning: statement has no effect [-Wunused-value]
    for(u1;u1<v1;u1++,u2++){
          ^