Run ID:92118

提交时间:2024-09-28 13:40:48

#include <iostream> using namespace std; int main(){ int sum1=1,sum2=0,n,m; cin>>n; for(int i=2;i<=n;i++){ if(i%2==0) sum1+=i; else sum1-=i; } cout<<sum1; return 0; }