Submission #969638

#	Time	Username	Problem	Language	Result	Execution time	Memory
969638		RandomUser	Savrsen (COCI17_savrsen)	C++17	120 / 120	1250 ms	49484 KiB

savrsen

#include <bits/stdc++.h>

#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
//#define int long long

using namespace std;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e7 + 5;
const double eps = 1e-9;

bool sieve[maxn+1];
int mpf[maxn+1];

ll exp(ll a, ll b) {
    ll ans = 1;
    while(b) {
        if(b & 1) ans = ans * a;
        a = a * a;
        b /= 2;
    }
    return ans;
}

int32_t main() {
    sieve[1] = 1;
    for(int i=2; i<=maxn; i++) {
        if(sieve[i]) continue;
        mpf[i] = i;
        for(int j=2*i; j<=maxn; j+=i) {
            sieve[j] = i;
            mpf[j] = i;
        }
    }

    int l, r;
    ll ans = 0;
    cin >> l >> r;

    for(int i=l; i<=r; i++) {
        map<int, int> cnt;
        int x = i;
        while(x > 1) {
            cnt[mpf[x]]++;
            x /= mpf[x];
        }

        ll div = 1;

        for(auto &[d, c] : cnt)
            div *= ((exp(d, c+1) - 1) / (d - 1));

        ans += abs((ll)i - (div - i));
    }

    cout << ans << '\n';
    return 0;
}

• Subtask 1: 120 / 120