Submission #857449

#	Time	Username	Problem	Language	Result	Execution time	Memory
857449		chanhchuong123	Rainforest Jumps (APIO21_jumps)	C++14	4 / 100	786 ms	45060 KiB

jumps

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

const int MAX = 200020;
int n, q;
stack<int> st;
int H[MAX], dp[18][MAX];
int rg[18][MAX], hg[18][MAX];
#define combine(x, y) (x == -1 ? y : y == -1 ? x : H[x] > H[y] ? x : y)

int getMax(int l, int r) {
    int k = 31 - __builtin_clz(r - l + 1);
    return combine(dp[k][l], dp[k][r - (1 << k) + 1]);
}

void init(int _n, vector<int> _H) {
    n = _n;
    for (int i = 0; i < n; ++i) {
        H[i] = _H[i];
    }

    st = stack<int> {};
    for (int i = 0; i <= n - 1; ++i) {
        while (st.size() && H[st.top()] < H[i]) st.pop();
        hg[0][i] = st.size() ? st.top() : -1; st.push(i);
    }
    st = stack<int> {};
    for (int i = n - 1; i >= 0; --i) {
        while (st.size() && H[st.top()] < H[i]) st.pop();
        rg[0][i] = st.size() ? st.top() : -1; st.push(i);
    }

    for (int i = 0; i < n; ++i) {
        dp[0][i] = i;
        hg[0][i] = combine(hg[0][i], rg[0][i]);
    }
    for (int j = 1; j <= 17; ++j) {
        for (int i = 0; i < n; ++i) {
            if (hg[j - 1][i] != -1) hg[j][i] = hg[j - 1][hg[j - 1][i]]; else hg[j][i] = -1;
            if (rg[j - 1][i] != -1) rg[j][i] = rg[j - 1][rg[j - 1][i]]; else rg[j][i] = -1;
            if (i + (1 << j) <= n) dp[j][i] = combine(dp[j - 1][i], dp[j - 1][i + (1 << j - 1)]);
        }
    }
}

int minimum_jumps(int A, int B, int C, int D) {
    int BC = getMax(B, C - 1), CD = getMax(C, D);
    if (H[BC] > H[CD]) return -1;
    int l = A - 1, r = B;
    while (r - l > 1) {
        int mid = l + r >> 1;
        if (H[getMax(mid, B)] < H[CD]) r = mid; else l = mid;
    }
    int st = getMax(r, B), res = 0;
    if (C <= rg[0][st] && rg[0][st] <= D) return 1;
    for (int j = 17; j >= 0; --j)           if (hg[j][st] != -1) {
        if (rg[0][hg[j][st]] != -1 && rg[0][hg[j][st]] < C) {
            st = hg[j][st];
            res += 1 << j;
        }
    }
    int nx = hg[0][st];
    if (rg[0][nx] <= D) {
        st = nx; ++res;
        if (C <= rg[0][nx] && rg[0][nx] <= D) return res + 1;
    }
    for (int j = 17; j >= 0; --j) if (rg[j][st] != -1) {
        if (rg[j][st] < C) {
            st = rg[j][st];
            res += 1 << j;
        }
    }
    res += 1; st = rg[0][st];
    if (st < C) return -1;
    if (st > D) return -1;
    return res;
}

Compilation message (stderr)

jumps.cpp: In function 'void init(int, std::vector<int>)':
jumps.cpp:42:91: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   42 |             if (i + (1 << j) <= n) dp[j][i] = combine(dp[j - 1][i], dp[j - 1][i + (1 << j - 1)]);
      |                                                                                         ~~^~~
jumps.cpp:10:34: note: in definition of macro 'combine'
   10 | #define combine(x, y) (x == -1 ? y : y == -1 ? x : H[x] > H[y] ? x : y)
      |                                  ^
jumps.cpp:42:91: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   42 |             if (i + (1 << j) <= n) dp[j][i] = combine(dp[j - 1][i], dp[j - 1][i + (1 << j - 1)]);
      |                                                                                         ~~^~~
jumps.cpp:10:38: note: in definition of macro 'combine'
   10 | #define combine(x, y) (x == -1 ? y : y == -1 ? x : H[x] > H[y] ? x : y)
      |                                      ^
jumps.cpp:42:91: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   42 |             if (i + (1 << j) <= n) dp[j][i] = combine(dp[j - 1][i], dp[j - 1][i + (1 << j - 1)]);
      |                                                                                         ~~^~~
jumps.cpp:10:61: note: in definition of macro 'combine'
   10 | #define combine(x, y) (x == -1 ? y : y == -1 ? x : H[x] > H[y] ? x : y)
      |                                                             ^
jumps.cpp:42:91: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   42 |             if (i + (1 << j) <= n) dp[j][i] = combine(dp[j - 1][i], dp[j - 1][i + (1 << j - 1)]);
      |                                                                                         ~~^~~
jumps.cpp:10:70: note: in definition of macro 'combine'
   10 | #define combine(x, y) (x == -1 ? y : y == -1 ? x : H[x] > H[y] ? x : y)
      |                                                                      ^
jumps.cpp: In function 'int minimum_jumps(int, int, int, int)':
jumps.cpp:52:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   52 |         int mid = l + r >> 1;
      |                   ~~^~~

• 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