/in/foo.c: In function 'main':
/in/foo.c:9:29: warning: left-hand operand of comma expression has no effect [-Wunused-value]
    9 |                 for(j=1;j<=i,j++)
      |                             ^
/in/foo.c:9:33: error: expected ';' before ')' token
    9 |                 for(j=1;j<=i,j++)
      |                                 ^
      |                                 ;