foo.c: In function 'cj':
foo.c:5:12: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    5 |     if(n>2 && !(n%2==1) || n<2)
      |        ~~~~^~~~~~~~~~~~
foo.c: In function 'main':
foo.c:14:15: warning: unused variable 'flag' [-Wunused-variable]
   14 |     int n,i,t,flag=0;
      |               ^~~~
foo.c:16:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务