题解 | #牛牛学数列#
牛牛学数列
https://www.nowcoder.com/practice/0b97367cd2184c12a0e02f7c223aee11
#include <stdio.h>
int main() {
int n; int sum = 0; int tmp;
while (scanf("%d", &n) != EOF) { // 注意 while 处理多个 case
for(int i=1; i<=n; i++){
tmp = i; //用一个变量暂存i的值
if(i % 2 == 0){//偶数则变成-i
tmp = -i;
}
sum = sum + tmp;//求和
}
printf("%d\n", sum);
}
return 0;
}
