foo.c: In function 'main':
foo.c:11:9: error: expected ')' before 'x'
   11 |  if(x1++x)
      |    ~    ^
      |         )
foo.c:13:2: warning: implicit declaration of function 'elseprintf'; did you mean 'vsnprintf'? [-Wimplicit-function-declaration]
   13 |  elseprintf("no");
      |  ^~~~~~~~~~
      |  vsnprintf
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务