Submission #559477

#	Time	Username	Problem	Language	Result	Execution time	Memory
559477		nghiass001	Rainforest Jumps (APIO21_jumps)	C++17	100 / 100	1152 ms	50516 KiB

jumps

#include <bits/stdc++.h>
#define FOR(i,l,r) for(int i=(l); i<=(r); ++i)
#define REP(i,l,r) for(int i=(l); i<(r); ++i)
#define FORD(i,r,l) for(int i=(r); i>=(l); --i)
#define REPD(i,r,l) for(int i=(r)-1; i>=(l); --i)
using namespace std;
const int N = 2e5 + 5, logN = 18, INF = 0x3c3c3c3c;
int n, a[N], lft[N][logN], rgt[N][logN], high[N][logN];
vector<int> S[N];

void init(int N, vector<int> H) {
    n = N + 2;
    REP(i, 1, n) a[i] = H[i - 1];
    a[0] = n; a[n] = n + 1;
    FOR(i, 0, n) rgt[i][0] = n;

    vector<int> Q;
    FOR(i, 0, n) {
        while (!Q.empty() && a[Q.back()] < a[i]) {
            rgt[Q.back()][0] = i;
            Q.pop_back();
        }
        if (Q.size()) lft[i][0] = Q.back();
        Q.push_back(i);
    }
    FOR(i, 0, n) high[i][0] = (a[lft[i][0]] > a[rgt[i][0]] ? lft[i][0] : rgt[i][0]);
    REP(j, 1, 18) FOR(i, 0, n) {
        lft[i][j] = lft[lft[i][j - 1]][j - 1];
        rgt[i][j] = rgt[rgt[i][j - 1]][j - 1];
        high[i][j] = high[high[i][j - 1]][j - 1];
    }
}

int minimum_jumps(int A, int B, int C, int D) {
    ++A; ++B; ++C; ++D;
    int pos = B;
    REPD(i, logN, 0) {
        int new_pos = lft[pos][i];
        if (A <= new_pos && rgt[new_pos][0] <= D) pos = new_pos;
    }
    if (C <= rgt[pos][0] && rgt[pos][0] <= D) return 1;
    int sum = 0;
    REPD(i, logN, 0) {
        int new_pos = high[pos][i];
        if (rgt[new_pos][0] < C) sum += 1 << i, pos = new_pos;
    }
    {
        int new_pos = high[pos][0];
        int new_sum = sum + 1;
        if (C <= rgt[new_pos][0] && rgt[new_pos][0] <= D) return new_sum + 1;
    }
    REPD(i, 18, 0) {
        int new_pos = rgt[pos][i];
        if (rgt[new_pos][0] < C) sum += 1 << i, pos = new_pos;
    }
    {
        int new_pos = rgt[pos][0];
        int new_sum = sum + 1;
        if (C <= rgt[new_pos][0] && rgt[new_pos][0] <= D) return new_sum + 1;
    }

    return -1;
}

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