foo.cc: In function 'int main()':
foo.cc:19:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("sortt.in","r",stdin);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:20:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("sortt.out","w",stdout);
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:22:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
foo.cc:23:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++)  scanf("%lf",&a[i]);
                            ~~~~~^~~~~~~~~~~~~

正在同步测试数据，请稍后
自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。