Submission #554074

#	Time	Username	Problem	Language	Result	Execution time	Memory
554074		Zhora_004	Rainforest Jumps (APIO21_jumps)	C++17	60 / 100	4006 ms	55824 KiB

jumps

#include "jumps.h"
#include <iostream>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <unordered_set>
#include <queue>
#include <deque>
#include <string>
#include <sstream>
#include <iomanip>
#include <map>
#include <unordered_map>
#include <stack>
#include <cstdio>
#include <climits>
#include <tuple>
#include <ctime>
#include <cstring>
#include <numeric>
#include <functional>
#include <chrono>
#include <cassert>
#include <bitset>
#include <fstream>
//#include <bit>
//#include <ranges>
//#include <numbers>
#define sz(a) ((int)((a).size()))
// printf("%.10f\n", ans);
/*ofstream fout("timeline.out");
ifstream fin("timeline.in");*/
using ll = long long;
using namespace std;
const int inf = 1e9;
bool task1;
int n, a, b, c, d, ans;
vector<int> h, dp, nge, pge, ind;
vector<vector<int>> go1, go2;

bool task(int id)
{
	if (id == 1)
	{
		for (int i = 0; i < n; i++) if (h[i] != i + 1) return 0;
		return 1;
	}
	return 0;
}

void NGE()
{
    stack<int> s;
    s.push(0);
    for (int i = 1; i < n; i++)
    {
        if (s.empty())
        {
            s.push(i);
            continue;
        }
        while (!s.empty() && h[s.top()] < h[i])
        {
            nge[s.top()] = i;
            s.pop();
        }
        s.push(i);
    }
    while (!s.empty())
    {
        nge[s.top()] = -1;
        s.pop();
    }
}

void PGE()
{
    stack<int> s;
    s.push(0);
    pge[0] = -1;
    for (int i = 1; i < n; i++)
    {
        while (!s.empty() && h[s.top()] < h[i]) s.pop();
        if (s.empty()) pge[i] = -1;
        else pge[i] = s.top();
        s.push(i);
    }
}

int dfs(int u)
{
    if (dp[u] != inf + 1) return dp[u];
    if (c <= u && u <= d) return dp[u] = 0;
    int r = nge[u];
    int ans = inf;
    if (r != -1) ans = min(ans, dfs(r) + 1);
    int l = pge[u];
    if (l != -1) ans = min(ans, dfs(l) + 1);
    return dp[u] = ans;
}

void init(int N, std::vector<int> H) {
	n = N;
	h = H;
	nge = pge = vector<int>(n);
    ind = vector<int>(n + 1);
    go1 = go2 = vector<vector<int>>(n, vector<int>(20));
	NGE();
	PGE();
    if (task(1)) task1 = 1;
    for (int i = 0; i < n; i++) ind[h[i]] = i;
    for (int i = n; i >= 1; i--)
    {
        int id = ind[i];
        int l = pge[id], r = nge[id];
        if (l == -1 || r == -1) go1[id][0] = n;
        else
        {
            if (h[l] > h[r]) go1[id][0] = l;
            else go1[id][0] = r;
        }
        for (int j = 1; j < 20; j++)
        {
            int u = go1[id][j - 1];
            if (u == n) go1[id][j] = n;
            else go1[id][j] = go1[u][j - 1];
        }
        if (l == -1 && r == -1) go2[id][0] = n;
        else if (l == -1) go2[id][0] = r;
        else if (r == -1) go2[id][0] = l;
        else
        {
            if (h[l] < h[r]) go2[id][0] = l;
            else go2[id][0] = r;
        }
        for (int j = 1; j < 20; j++)
        {
            int u = go2[id][j - 1];
            if (u == n) go2[id][j] = n;
            else go2[id][j] = go2[u][j - 1];
        }
    }
}


int minimum_jumps(int A, int B, int C, int D) {
	a = A, b = B, c = C, d = D;
	if (task1) return c - b;
    if (a == b && c == d)
    {
        if (h[a] > h[c]) return -1;
        int ans = 0, id = a;
        for (int i = 19; i >= 0; i--)
        {
            int u = go1[id][i];
            if (u < n && h[u] <= h[c])
            {
                ans += (1 << i);
                id = u;
            }
        }
        for (int i = 19; i >= 0; i--)
        {
            int u = go2[id][i];
            if (u < n && h[u] <= h[c])
            {
                ans += (1 << i);
                id = u;
            }
        }
        if (id == c) return ans;
        else return -1;
    }
	else
	{
        dp = vector<int>(n, inf + 1);
        ans = inf;
        for (int i = a; i <= b; i++) ans = min(ans, dfs(i));
        if (ans == inf) ans = -1;
        return ans;
	}
}

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