题解 | #牛牛学数列#
牛牛学数列
http://www.nowcoder.com/practice/0b97367cd2184c12a0e02f7c223aee11
#include <stdio.h>
int main(){
int n,sum=0;
scanf("%d",&n);
for(int i=1;i<=n;i++){
if(i%2==0){
sum+=-i;
continue;
}
sum+=i;
}
printf("%d",sum);
return 0;
}
int main(){
int n,sum=0;
scanf("%d",&n);
for(int i=1;i<=n;i++){
if(i%2==0){
sum+=-i;
continue;
}
sum+=i;
}
printf("%d",sum);
return 0;
}
