foo.c: In function ‘main’:
foo.c:10:33: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   10 |                 for(num=1;num<=b,num++)
      |                                 ^
foo.c:10:39: error: expected ‘;’ before ‘)’ token
   10 |                 for(num=1;num<=b,num++)
      |                                       ^
      |                                       ;