Question

用c语言写程序 1的平方+2的平方+3的平方+。。。。。（n-1）的平方+n的平方要求写出函数和主函数。

递归函数原型为：long dg(int n);

Answer 1

#include <stdio.h>

long dg(int n)
{
if (n == 1)
return 1;
else {
int tmp = dg(n - 1);
int result = n * n + tmp;
return result;
}
}

int main(void)
{
int i;
for (i = 1; i <= 20; ++i)
printf("dg(%d)=%ld\n", i, dg(i));
return 0;
}

Answer 2

# include “stdio.h”
long fun(int n)
{int i;long s=0;
for(i=0;i<=n;i++)
s=s+i*i;
return s;
｝
main()
{ int n;long t;
scanf("%d",&n);
t=fun(n);
printf("%ld",t);

}

Answer 3

int suan(int i);
int main()
{
int i;
scanf("%d",&i);
printf("%d",suan(i));
}
int suan(int i)
{
int d = 0;
while(i!=0)
{
d = i*i;
i--;
}
return d;
}