C语言入门题，来个大lao看看

Question

Answer 1

#include <stdio.h>
#include <math.h>
int main()
{
int i,n;
double t,sum=0;
printf("请输入正整数n:");
scanf("%d",&n);

for(i=1;i<=n;i++)
{
    t += sqrt(i);
    sum += t;    
}
    
printf("sum=%lf\n",sum); 
return 0;

}