제출 #1067755

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1067755		Whisper	Fire (BOI24_fire)	C++17	100 / 100	186 ms	79504 KiB

Main

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, a) for (int i = 0; i < (a); ++i)
#define REPD(i, a) for (int i = (a) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
#define MAX             200005
#define LOG                 20
int nArr, maxTime;

struct Info{
    int l, r;
    Info(){}
    Info(int _l, int _r): l(_l), r(_r){}

    bool operator < (const Info &oth) const{
        if(l != oth.l)
            return l < oth.l;
        return r < oth.r;
    }
} A[MAX];

int up[MAX][LOG], sum[MAX][LOG];

void process(void){
    cin >> nArr >> maxTime;
    for (int i = 1; i <= nArr; ++i){
        cin >> A[i].l >> A[i].r;
        if(A[i].l > A[i].r) A[i].r += maxTime;
    }
    sort(A + 1, A + nArr + 1);

    set<pair<int, int>> mySet;
    int j = 1;
    for (int i = 1; i <= nArr; ++i){
        while (j <= nArr && A[j].l <= A[i].r){
            mySet.insert(make_pair(A[j].r, j));
            ++j;
        }

        pair<int, int> nxt = *mySet.rbegin();
        up[i][0] = nxt.second;
        sum[i][0] = (nxt.first - A[i].r);

        mySet.erase(make_pair(A[i].r, i));
    }

    for (int i = 1; i < LOG; ++i){
        for (int u = 1; u <= nArr; ++u){
            up[u][i] = up[up[u][i - 1]][i - 1];
            sum[u][i] = sum[u][i - 1] + sum[up[u][i - 1]][i - 1];
        }
    }

    int ans = INF;

    for (int i = 1; i <= nArr; ++i){
        int l = i, sm = A[i].r - A[i].l;
        int res = 1;
        for (int j = LOG - 1; j >= 0; --j){
            if(up[l][j] > 0 && sm + sum[l][j] < maxTime){
                sm += sum[l][j];
                res += MASK(j);
                l = up[l][j];
            }
        }
        ++res;
        sm += sum[l][0];
        if (sm >= maxTime){
            minimize(ans, res);
        }
    }
    cout << (ans >= INF ? -1 : ans);
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    process();
    return (0 ^ 0);
}

• Subtask 1: 14 / 14
• Subtask 2: 17 / 17
• Subtask 3: 9 / 9
• Subtask 4: 13 / 13
• Subtask 5: 21 / 21
• Subtask 6: 26 / 26