#include<bits/stdc++.h> using namespace std; int main(){ int n,ans=0; cin>>n; for(int i=1;i<=n;i++){ ans+=i*i; } cout<<ans; return 0; } /************************************************************** Problem: 1054 User: liujinhao Language: C++ Result: Accepted Time:9 ms Memory:2072 kb ****************************************************************/