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- /*
- _____ _ _ _ _
- |_ _| |__ ___ / \ _ __ ___| |__ _ _| |
- | | | '_ \ / _ \ / _ \ | '_ \/ __| '_ \| | | | |
- | | | | | | __// ___ \| | | \__ \ | | | |_| | |
- |_| |_| |_|\___/_/ \_\_| |_|___/_| |_|\__,_|_|
- */
- #include<bits/stdc++.h>
- #include <ext/pb_ds/assoc_container.hpp>
- #include <ext/pb_ds/tree_policy.hpp>
- #define ll long long
- #define pb push_back
- #define ppb pop_back
- #define endl '\n'
- #define mii map<ll,ll>
- #define msi map<string,ll>
- #define mis map<ll, string>
- #define rep(i,a,b) for(ll i=a;i<b;i++)
- #define repr(i,a,b) for(ll i=b-1;i>=a;i--)
- #define trav(a, x) for(auto& a : x)
- #define pii pair<ll,ll>
- #define vi vector<ll>
- #define vii vector<pair<ll, ll>>
- #define vs vector<string>
- #define all(a) (a).begin(),(a).end()
- #define F first
- #define S second
- #define sz(x) (ll)x.size()
- #define hell 1000000007
- #define lbnd lower_bound
- #define ubnd upper_bound
- #define max(a,b) (a>b?a:b)
- #define min(a,b) (a<b?a:b)
- /* For Debugging */
- #define DEBUG cerr<<"\n>>>I'm Here<<<\n"<<endl;
- #define display(x) trav(a,x) cout<<a<<" ";cout<<endl;
- #define what_is(x) cerr << #x << " is " << x << endl;
- std::mt19937_64 rng(std::chrono::steady_clock::now().time_since_epoch().count());
- #define ordered_set tree<ll, null_type,less<ll>, rb_tree_tag,tree_order_statistics_node_update>
- #define TIME cerr << "\nTime elapsed: " << setprecision(5) <<1000.0 * clock() / CLOCKS_PER_SEC << "ms\n";
- #define DECIMAL(n) cout << fixed ; cout << setprecision(n);
- #define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
- using namespace __gnu_pbds;
- using namespace std;
- #define PI 3.141592653589793
- #define N 100005
- ll add(ll a,ll b,ll mod=hell)
- {
- return (a+b)%mod;
- }
- ll sub(ll a,ll b,ll mod=hell)
- {
- return (a-b+mod)%mod;
- }
- ll mul(ll a,ll b,ll mod=hell)
- {
- a=a%hell;
- b=b%hell;
- return (a*b)%mod;
- }
- ll expo(ll base, ll exponent, ll mod) { //return base^exponent modulo modulus
- ll ans = 1;
- while(exponent !=0 ) {
- if((exponent&1) == 1) {
- ans = ans*base ;
- ans = ans%mod;
- }
- base = base*base;
- base %= mod;
- exponent>>= 1;
- }
- return ans%mod;
- }
- void solve()
- {
- ll n;
- cin>>n;
- ll ans=0,vl;
- ll modi=expo(2,hell-2,hell);
- for (ll i = 1, la; i <= n; i = la + 1)
- {
- la = n / (n / i);
- vl=mul(sub(mul(la,(la+1)),mul(i,(i-1+hell))),modi);
- vl=mul(vl,(n/i));
- ans=add(ans,vl);
- }
- cout<<ans<<endl;
- return;
- }
- int main()
- {
- FAST
- int TESTS=1;
- // cin>>TESTS;
- while(TESTS--)
- {
- solve();
- }
- TIME
- return 0;
- }
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