/in/foo.c: In function 'main':
/in/foo.c:5:9: warning: right-hand operand of comma expression has no effect [-Wunused-value]
  for(b=1,a,n;b<=a;b++)
         ^
/in/foo.c:5:11: warning: right-hand operand of comma expression has no effect [-Wunused-value]
  for(b=1,a,n;b<=a;b++)
           ^
/in/foo.c:9:2: error: expected ';' before '}' token
  }
  ^
/in/foo.c:10:5: error: expected '(' before 'n'
  if n>2
     ^
/in/foo.c:10:5: warning: statement with no effect [-Wunused-value]