제출 #1194883

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1194883		browntoad	Rainforest Jumps (APIO21_jumps)	C++20	4 / 100	435 ms	45760 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
// #define int ll
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define REP(i, n) FOR(i, 0, n) 
#define REP1(i, n) FOR(i, 1, n+1)
#define RREP(i, n) for (int i = (n)-1; i >= 0; i--)
#define pii pair<int, int>
#define f first
#define s second
#define pb push_back
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) (int)((x).size())

namespace{
    const ll maxn = 2e5+5;
    const ll mxpw = 18;
    int smaxR[maxn][mxpw];
    int smaxL[maxn][mxpw];

    int jump[maxn][mxpw]; // where i jump to
    vector<int> h(maxn);
    int n;
}

void init(int N, std::vector<int> H) {
    n = N;
    REP(i, n) h[i] = H[i];
    
    REP(i, n){
        smaxL[i][0] = H[i];
        REP1(j, mxpw-1){
            smaxL[i][j] = max(smaxL[i][j-1], smaxL[max(0, i-(1<<j-1))][j-1]);
        }
    }
    RREP(i, n){
        smaxR[i][0] = H[i];
        REP1(j, mxpw-1){
            smaxR[i][j] = max(smaxR[i][j-1], smaxR[min(n-1, i+(1<<j-1))][j-1]);
        }
    }

    stack<int> st;
    RREP(i, n){
        while(SZ(st) && h[st.top()] < h[i]) st.pop();
        if (!SZ(st)){
            jump[i][0] = i; // itself
        }
        else{
            jump[i][0] = st.top();
        }
        st.push(i);
    }
    RREP(i, n){
        REP1(j, mxpw-1){
            jump[i][j] = jump[jump[i][j-1]][j-1];
        }
    }
}

int mxH(int l, int r){
    if (l > r) return 0;
    int p = log2(r-l+1);
    return max(smaxR[l][p], smaxL[r][p]);
}


int minimum_jumps(int A, int B, int C, int D){
    if (h[B] > mxH(C, D)) return -1;
    if (mxH(B+1, C-1) > mxH(C, D)) return -1;
    int mxCD = mxH(C, D);

    int l = A, r = B;
    while(l < r){
        int mid = l+r>>1;
        if (mxH(mid, B) < mxCD) r = mid;
        else l = mid+1;
    }
    int tmp = mxH(l, B);
    r = B;
    while(l < r){
        int mid = l+r+1>>1;
        if (mxH(mid, B) == tmp) l = mid;
        else r = mid-1;
    }

    int cnt = 1, cur = l;
    RREP(i, mxpw){
        if (jump[cur][i] < C){
            cnt += (1<<i);
            cur = jump[cur][i];
        }
    }
    return cnt;
}

• Subtask 1: 4 / 4
• Subtask 2: 0 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 12
• Subtask 5: 0 / 23
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19