#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;
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());
}
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 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]);
}
}
int minimum_jumps(int A, int B, int C, int D)
{
a = A, b = B, c = C, d = 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);
}
int main() {
int n; cin >> n;
vector<int> h(n);
for (int& x : h) cin >> x;
init(n, h);
int q; cin >> q;
while (q--) {
cin >> a >> b >> c >> d;
cout << minimum_jumps(a, b, c, d) << endl;
}
}
Compilation message
jumps.cpp: In function 'std::vector<int> pge_(std::vector<int>)':
jumps.cpp:17:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
17 | for (int i = 1; i < v.size(); i++)
| ~~^~~~~~~~~~
/usr/bin/ld: /tmp/cc6jNook.o: in function `main':
stub.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccISAZpo.o:jumps.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
