Submission #1200743

#	Time	Username	Problem	Language	Result	Execution time	Memory
1200743		yeediot	Rainforest Jumps (APIO21_jumps)	C++20	4 / 100	497 ms	34848 KiB

jumps

#include<bits/stdc++.h>
using namespace std;
#ifndef local
#include "jumps.h"
#endif
#define F first
#define S second
#define double long double
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
const int mxn = 2e5 + 5;
int n, h[mxn], l[20][mxn], r[20][mxn];
void init(int N, std::vector<int> H) {
    n = N;
    for(int i = 1; i <= n; i++){
        h[i] = H[i - 1];
    }
    vector<int>st;
    for(int i = 1; i <= n; i++){
        while(sz(st) and h[st.back()] < h[i]) st.pop_back();
        l[0][i] = sz(st) ? st.back() : i;
        st.pb(i);
    }
    st.clear();
    r[0][n + 1] = n + 1;
    l[0][n + 1] = n + 1;
    for(int i = n; i > 0; i--){
        while(sz(st) and h[st.back()] < h[i]) st.pop_back();
        r[0][i] = sz(st) ? st.back() : i;
        st.pb(i);
    }
    for(int i = 1; i < 20; i++){
        for(int j = 0; j <= n + 1; j++){
            l[i][j] = min(l[i - 1][l[i - 1][j]], l[i - 1][r[i - 1][j]]);
            r[i][j] = max(r[i - 1][r[i - 1][j]], r[i - 1][l[i - 1][j]]);
            //cout << i << ' ' << j << ' ' << l[i][j] << ' ' << r[i][j] << '\n';
        }
    }
}
int minimum_jumps(int A, int B, int C, int D) {
    A++, B++, C++, D++;
    int L = A, R = B, ans = 0;
    for(int i = 19; i >= 0; i--){
        int nl = min(l[i][L], l[i][R]);
        int nr = max(r[i][L], r[i][R]);
        //cout << nl << ' ' << nr << '\n';
        if(nr < C){
            ans += (1 << i);
            L = nl, R = nr;
        }
    }
    if(r[0][R] == C or r[0][L] == C){
        return ans + 1;
    }
    return -1;
}

#ifdef local
int main() {
    freopen("/Users/iantsai/cpp/input.txt","r",stdin);
    freopen("/Users/iantsai/cpp/output.txt","w",stdout);
  int N, Q;
  assert(2 == scanf("%d %d", &N, &Q));
  std::vector<int> H(N);
  for (int i = 0; i < N; ++i) {
    assert(1 == scanf("%d", &H[i]));
  }
  init(N, H);

  for (int i = 0; i < Q; ++i) {
    int A, B, C, D;
    assert(4 == scanf("%d %d %d %d", &A, &B, &C, &D));
    printf("%d\n", minimum_jumps(A, B, C, D));
  }
  return 0;
}
#endif

• 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