Submission #240099

#	Time	Username	Problem	Language	Result	Execution time	Memory
240099		wiwiho	Strange Device (APIO19_strange_device)	C++14	100 / 100	904 ms	45892 KiB

strange_device

//#define NDEBUG

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define iceil(a, b) ((a + b - 1) / b)
#define tomax(a, b) (a = max(a, b))
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}

//#define TEST

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;

const ll MOD = 1000000007;
const ll MAX = 2147483647;

template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}

int main(){
    StarBurstStream

    int n;
    cin >> n;

    ll a, b;
    cin >> a >> b;

    ll x = a / __gcd(a, b + 1);
    ll t = x > iceil((1LL << 60), b) ? (1LL << 60) : x * b;

    vector<pll> e;
    for(int i = 0; i < n; i++){

        ll l, r;
        cin >> l >> r;

        if(r - l + 1 >= t){
            cout << t << "\n";
            return 0;
        }

        if(l % t <= r % t){
            e.eb(mp(l % t, 1));
            e.eb(mp(r % t + 1, 0));
        }
        else{
            e.eb(mp(l % t, 1));
            e.eb(mp(t, 0));
            e.eb(mp(0, 1));
            e.eb(mp(r % t + 1, 0));
        }
    }

//    cerr << t << "\n";

    ll ans = 0, lst = -1;
    int cnt = 0;
    lsort(e);

    for(pll i : e){
//        cerr << i.F << " " << i.S << " " << lst << "\n";
        if(i.S){
            cnt++;
            if(lst == -1) lst = i.F;
        }
        else{
            cnt--;
            if(cnt == 0){
//                cerr << "test " << lst << " " << i.F << "\n";
                ans += i.F - lst;
                lst = -1;
            }
        }
//        cerr << cnt << " " << ans << "\n";
    }

    cout << ans << "\n";

    return 0;
}

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