#include <stdio.h>
int main()
{
int sum,n,i
scanf("%d",&n)
for(sum=0,i=1i<=ni+=2)
sum+=i
printf("%d\n",sum)
return 0
}
#include<stdio.h>int main(){
int n,i
long a,sum = 1
scanf("%ld",&n)
for(i = 3,a = 1i <= ni += 2)
{
a *= i * (i - 1)
sum += a
}
printf("%ld\n",sum)
return 0
}
本程序已经在VC上运行通过,在N不是很大的情况下可以,太大了就属于大数问题了,要改
# include <stdio.h>long Test(int n)
int main(void)
{
printf("%ld\n",Test(7))
return 0
}
long Test(int n) //注意n只能是奇数
{
if (n == 1)
return 1
return n+Test(n-2)
}