题解 | #牛牛学数列#
牛牛学数列
https://ac.nowcoder.com/acm/problem/22156
#include<bits/stdc++.h> using namespace std; int main() { int n;cin>>n; int sum=0; int sum2=0; for(int i=0;i<=n;i++) { if(i%2==1) { sum+=i; } if(i%2==0) { sum2+=i; } } cout<<(sum2-sum)*-1; }
