Submission #247998

#	Time	Username	Problem	Language	Result	Execution time	Memory
247998		NONAME	Savrsen (COCI17_savrsen)	C++14	120 / 120	1235 ms	78656 KiB

savrsen

#include <bits/stdc++.h>
#define dbg(x) cerr << #x << " = " << x << "\n"
#define fast_io ios_base::sync_with_stdio(0); cin.tie(0); cout.tie()
using namespace std;
using ll = long long;

ll A, B, f[int(1e7) + 10];

int main() {
    fast_io;

    cin >> A >> B;
    for (int i = 1; i <= B; ++i)
        f[i] = i;

    for (int i = 1; i <= B; ++i)
    for (int j = 2 * i; j <= B; j += i)
        f[j] -= i;

    for (int i = 1; i <= B; ++i)
        f[i] = abs(f[i]);

    ll ans = 0;
    for (int i = A; i <= B; ++i)
        ans += f[i];

    cout << ans << "\n";
}

• Subtask 1: 120 / 120