foo.cc: In function 'int main()':
foo.cc:12:22: warning: for increment expression has no effect [-Wunused-value]
    for(int j=i;j<=n;j+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。