题解 | #等差数列#
等差数列
https://www.nowcoder.com/practice/f792cb014ed0474fb8f53389e7d9c07f
#include <stdio.h>
int main(void)
{
int n = 0;
int num =2;
int sum = 0;
scanf("%d",&n);
while(n--){
sum += num;
num+=3;
}
printf("%d",sum);
return 0;
}
