제출 #398385

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
398385		jack715	이상한 기계 (APIO19_strange_device)	C++14	65 / 100	591 ms	16928 KiB

strange_device

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define pp pop_back
#define mp make_pair
#define bb back
#define ff first
#define ss second
#define int long long

using namespace std;

/*
 ____     __    _______    _______   __________
|     \  |  |  |  _____|  /  _____) |____  ____|
|  |\  \ |  |  | |__     (  (_____      |  |
|  | \  \|  |  |  __|     \_____  \     |  | 
|  |  \     |  | |_____    _____)  )    |  | 
|__|   \____|  |_______|  (_______/     |__| 
*/

int INF = LLONG_MAX;

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int n, A, B, I, gcd, k, l, r;
    cin >> n >> A >> B;
    gcd = __gcd(A, B+1);

    if (gcd == 1) k = A;
    else k = A / gcd;

    if (INF / k <= B) 
        I = INF;
    else 
        I = k*B;

    vector<pair<int, int> > rem;
    for (int i = 0; i < n; i++) {
        cin >> l >> r;
        if (r-l >= I) {
            rem.pb({0, I});
        } else if (l%I > r%I) {
            rem.pb({l%I, I-1});
            rem.pb({0, r%I});
        } else {
            rem.pb({l%I, r%I});
        } 
    }

    int L = 0, ans = 0;
    sort(rem.begin(), rem.end());
    for (auto el : rem) {
        el.ff = max(el.ff, L);
        if (el.ff > el.ss)
            continue;
        ans += el.ss-el.ff+1;
        L = max(L, el.ss+1);
    }
    cout << ans << '\n';
    return 0;
}

/* stuff you should look for
    * int overflow, array bounds
    * special cases (n=1?)
    * do smth instead of nothing and stay organized
    * WRITE STUFF DOWN
    * DON'T GET STUCK ON ONE APPROACH
*/

• Subtask 1: 10 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 0 / 30