王小二切餅
Problem Description
Input
Output
Example Input
100
Example Output
5051
Hint
Author
參考代碼
#include<stdio.h>
int f(int n)
{
if( n > 1 )
n += f(n - 1);
return n;
}
int main()
{
int n;
while(~scanf("%d",&n))
printf("%d\n",f(n)+1);
return 0;
}