Submission #258394

#	Time	Username	Problem	Language	Result	Execution time	Memory
258394		DS007	Strange Device (APIO19_strange_device)	C++14	35 / 100	850 ms	33592 KiB

strange_device

#include <bits/stdc++.h>
using namespace std;
#define int long long

int n, a, b;

bool overflow(int x, int y) {
    int result = x * y;
    return result / x != y;
}

int sum() {
    int ans = 0;
    for (int i = 0; i < n; i++) {
        int l, r;
        cin >> l >> r;
        ans += r - l + 1;
    }
    return ans;
}

int solveTestCase() {
    cin >> n >> a >> b;

    int temp = a / __gcd(a, b + 1);
    assert(a % __gcd(a, b + 1) == 0);
    if (overflow(temp, b))
        return cout << sum(), 0;

    temp *= b;
    //cerr << temp << "\n";
    vector<pair<int, int>> v;

    for (int i = 0; i < n; i++) {
        int l, r;
        cin >> l >> r;

        if (r - l + 1 >= temp)
            return cout << temp, 0;

        if (l % temp <= r % temp)
            v.emplace_back(l % temp, 1), v.emplace_back(r % temp + 1, 2);
        else
            v.emplace_back(l % temp, 1), v.emplace_back(temp, 2), v.emplace_back(0, 1), v.emplace_back(r % temp + 1, 2), assert(l % temp > r % temp + 1);
    }

    sort(v.begin(), v.end());

    int ans = 0, d = 0, last = 0;
    for (auto i : v) {
        if (d == 0)
            last = i.first;

        if (i.second == 1)
            d++;
        else
            d--;

        assert(d >= 0);
        if (d == 0)
            ans += i.first - last;
    }

    cout << ans;
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int t = 1;
    //cin >> t;
    while (t--)
        solveTestCase();
}

Compilation message (stderr)

strange_device.cpp: In function 'long long int solveTestCase()':
strange_device.cpp:65:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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