| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 672298 | Vahe | Rainforest Jumps (APIO21_jumps) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "jumps.h"
#include <iostream>
#include <algorithm>
#include <vector>
#include <stack>
using namespace std;
int n, a, b, c, d;
vector<int> h, pge, nge, dp;
vector<vector<int>> gp;
bool arajitest = 1;
vector<vector<int>> up1, up2;
vector<int> pge_(vector<int> v)
{
vector<int> tmp(v.size());
stack<int> s;
s.push(0);
tmp[0] = -1;
for (int i = 1; i < v.size(); i++)
{
while (!s.empty() && v[s.top()] < v[i]) s.pop();
tmp[i] = (s.empty() ? -1 : s.top());
s.push(i);
}
return tmp;
}
vector<int> nge_(vector<int> v)
{
stack<int> s;
vector<int> tmp(v.size(), -1);
for (int i = 0; i < n; i++)
{
while (!s.empty() && v[s.top()] < v[i]) tmp[s.top()] = i, s.pop();
s.push(i);
}
return tmp;
}
void dfs(int u)
{
if (u >= c && u <= d) { dp[u] = 0; return; }
if (dp[u] != 2e9) return;
if (gp[u].size() > 0) dfs(gp[u][0]);
if (gp[u].size() > 1) dfs(gp[u][1]);
int x = (gp[u].size() > 0 ? dp[gp[u][0]] : 2e9);
int y = (gp[u].size() > 1 ? dp[gp[u][1]] : 2e9);
dp[u] = min(x, y) + 1;
}
void make1(int u, int p)
{
up1[u][0] = p;
for (int i = 1; i < 20; i++) up1[u][i - 1] != 2e9 ? up1[u][i] = up1[up1[u][i - 1]][i - 1] : (int)"Gven_";
int x = (gp[u].size() > 0 ? gp[u][0] : 2e9);
int y = (gp[u].size() > 1 ? gp[u][1] : 2e9);
if (min(x, y) != 2e9) make1(min(x, y), u);
}
void make2(int u, int p)
{
up2[u][0] = p;
for (int i = 1; i < 20; i++) up2[u][i - 1] != 2e9 ? up2[u][i] = up2[up2[u][i - 1]][i - 1] : (int)"Klep_";
int x = (gp[u].size() > 0 ? gp[u][0] : 2e9);
int y = (gp[u].size() > 1 ? gp[u][1] : 2e9);
if (max(x, y) != 2e9) make2(max(x, y), u);
else if (min(x, y) != 2e9) make2(min(x, y), u);
}
void init(int N, vector<int> H)
{
n = N;
h = H;
pge = pge_(H);
nge = nge_(H);
gp = vector<vector<int>>(n);
for (int i = 0; i < n; i++)
{
if (pge[i] != -1) gp[i].push_back(pge[i]);
if (nge[i] != -1) gp[i].push_back(nge[i]);
}
for (int i = 0; i < n; i++) if (H[i] != i + 1) arajitest = 0;
}
int minimum_jumps(int A, int B, int C, int D)
{
a = A, b = B, c = C, d = D;
if (arajitest) return C - B;
else if (a != b && c != d) {
dp = vector<int>(n, 2e9);
int mn = 2e9;
for (int i = a; i <= b; i++) dfs(i), mn = min(mn, dp[i]);
return (mn >= 2e9 ? -1 : mn);
}
else {
up1 = up2 = vector<vector<int>>(n, vector<int>(20, 2e9));
make1(A, 2e9);
make2(A, 2e9);
int G = A, len = 0;
for (int i = 19; i >= 0; i--)
{
if (h[up2[G][i]] <= h[C]) G = up2[G][i], len += (1 << i);
}
if (G == C) return len;
for (int i = 19; i >= 0; i--)
{
if (h[up1[G][i]] <= h[C]) G = up1[G][i], len += (1 << i);
}
return G == C ? len : -1;
}
}