Codeforces Round #422 (Div. 2), problem: (D) My pretty girl Noora Solution In C/C++

By | 2017-07-25T09:02:47+00:00 July 25th, 2017|Categories: C/C++, Programming|Tags: , , , , , , , |

#include<bits/stdc++.h> using namespace std; long long f[5000010],pwr[5000010],mod=1e9+7,t,r,l,ans; main() { int i,j,k; cin>>t>>l>>r; pwr[0]=1; //for(i=1;i<=r-l+1;i++)pwr[i]=(1ll*pwr[i-1]*t)%mod; for(i=0;i<=r;i++) f[i]=1e18; f[1]=0; for(i=1;i<=r;i++) { for(j=2*i,k=2;j<=r;j+=i,k++) { f[j]=min(f[j],(1ll*i*(k-1)*k)/2+f[i]); } } ans=0;long long pr=1; for(i=l;i<=r;i++) ans=(ans+((f[i])%mod*pr)%mod)%mod,pr=(pr*t)%mod; cout<<ans<<endl; }