제출 #737284

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
737284		phoebe	Rainforest Jumps (APIO21_jumps)	C++17	0 / 100	4089 ms	17436 KiB

jumps

#include <bits/stdc++.h>
#include "jumps.h"
using namespace std;

#define ll long long
#define pii pair<int, int>
#define F first
#define S second
#define FOR(i, n) for (int i = 0; i < n; i++)
#define PB push_back

const int maxn = 2e5 + 10, INF = 1e9 + 7;
int n, h[maxn], tree[maxn * 4], jump[maxn][20];

void build(int tl = 0, int tr = maxn, int i = 1){
    if (tl == tr){
        tree[i] = tl; return;
    }
    int tm = (tl + tr) / 2;
    build(tl, tm, i * 2); build(tm + 1, tr, i * 2 + 1);
    tree[i] = (h[tree[i * 2]] < h[tree[i * 2 + 1]] ? 
    tree[i * 2] : tree[i * 2 + 1]);
}

int solve(int s, int e){
    int re = 0;
    for (int p = 19; p >= 0; p--){
        if (jump[s][p] < e) re += (1<<p), s = jump[s][p];
    }
    re++; s = jump[s][0];
    if (s == e) return re;
    return INF;
}

void init(int N, vector<int> H){
    fill(h, h + maxn, INF);
    n = N;
    FOR(i, n) h[i] = H[i];
    build();
    stack<int> s;
    for (int i = n - 1; i >= 0; i--){
        while (!s.empty() && h[s.top()] < h[i]) s.pop();
        jump[i][0] = (s.empty() ? i : s.top());
        s.push(i);
    }
    for (int p = 1; p < 20; p++){
        FOR(i, n) jump[i][p] = jump[jump[i][p - 1]][p - 1];
    }
}

int minimum_jumps(int a, int b, int c, int d){
    int re = INF;
    for (int i = a; i <= b; i++){
        for (int j = c; j <= d; j++){
            re = min(re, solve(i, j));
        }
    }
    return (re != INF ? re : -1);
}

• Subtask 1: 0 / 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