/in/foo.c: In function 'main':
/in/foo.c:5:12: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    5 |   for(i=100,i<=999,i++){
      |            ^
/in/foo.c:5:23: error: expected ';' before ')' token
    5 |   for(i=100,i<=999,i++){
      |                       ^
      |                       ;
/in/foo.c:5:23: error: expected expression before ')' token