/in/foo.c: In function 'main':
/in/foo.c:5:26: error: expected expression before ',' token
    5 |         scanf("%d %d",&a,,&n);
      |                          ^
/in/foo.c:9:16: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    9 |         for(i=1,i<=n,i++){
      |                ^
/in/foo.c:9:25: error: expected ';' before ')' token
    9 |         for(i=1,i<=n,i++){
      |                         ^
      |                         ;
/in/foo.c:9:25: error: expected expression before ')' token