oj.uz

Submission #438100

# Submission time Handle Problem Language Result Execution time Memory
438100 2021-06-27T14:33:10 Z cheeheng Rainforest Jumps (APIO21_jumps) C++14
4 / 100
 1840 ms 83376 KB 
#include "jumps.h"
#include <bits/stdc++.h>
using namespace std;

typedef pair<int, int> ii;

int nextGreater[200005][20];
int prevGreater[200005][20];
int indx[200005];
int log2_[200005];
ii val[200005][20];
int best[200005][20];
int A1[200005];

int M;

void init2(){
    for(int i = 0; i < M; i ++){
        val[i][0] = ii(A1[i], i);
    }

    for(int k = 1; k < 20; k ++){
        for(int i = 0; i <= M-(1<<k); i ++){
            val[i][k] = max(val[i][k-1], val[i+(1<<(k-1))][k-1]);
        }
    }

    log2_[1] = 0;
    for(int i = 2; i <= M; i ++){
        log2_[i] = log2_[i>>1] + 1;
    }
}

ii findMax(int l, int r){
    int k = log2_[r-l+1];
    return max(val[l][k], val[r-(1<<k)+1][k]);
}

void init(int N, std::vector<int> H){
    M = N;

    for(int i = 0; i < N; i ++){
        A1[i] = H[i];
    }

    init2();

    for(int i = 0; i < N; i ++){
        nextGreater[i][0] = N;
        prevGreater[i][0] = -1;
    }

    vector<ii> stack1 = vector<ii>();
    for(int i = 0; i < N; i ++){
        while(!stack1.empty()){
            ii temp = stack1.back();

            if(temp.first < H[i]){
                nextGreater[temp.second][0] = i;
                stack1.pop_back();
            }else{
                break;
            }
        }
        stack1.emplace_back(H[i], i);
    }

    stack1 = vector<ii>();
    for(int i = N-1; i >= 0; i --){
        while(!stack1.empty()){
            ii temp = stack1.back();

            if(temp.first < H[i]){
                prevGreater[temp.second][0] = i;
                stack1.pop_back();
            }else{
                break;
            }
        }
        stack1.emplace_back(H[i], i);
    }

    /*for(int i = 0; i < N; i ++){
        printf("nextGreater[%d]=%d\n", i, nextGreater[i][0]);
    }

    for(int i = 0; i < N; i ++){
        printf("prevGreater[%d]=%d\n", i, prevGreater[i][0]);
    }*/

    for(int k = 1; k < 20; k ++){
        for(int i = 0; i < N; i ++){
            if(nextGreater[i][k-1] == N){
                nextGreater[i][k] = N;
            }else{
                nextGreater[i][k] = nextGreater[nextGreater[i][k-1]][k-1];
            }

            if(prevGreater[i][k-1] == -1){
                prevGreater[i][k] = -1;
            }else{
                prevGreater[i][k] = prevGreater[prevGreater[i][k-1]][k-1];
            }
        }
    }

    for(int i = 0; i < N; i ++){
        int X2 = i;
        int X3, X4;
        if(prevGreater[X2][0] == -1){
            X3 = nextGreater[X2][0];
            X4 = prevGreater[X2][0];
        }else if(nextGreater[X2][0] == N){
            X3 = prevGreater[X2][0];
            X4 = nextGreater[X2][0];
        }else if(A1[prevGreater[X2][0]] > A1[nextGreater[X2][0]]){
            X3 = prevGreater[X2][0];
            X4 = nextGreater[X2][0];
        }else{
            X3 = nextGreater[X2][0];
            X4 = prevGreater[X2][0];
        }
        best[i][0] = X3;
        if(best[i][0] == N){best[i][0] = -1;}
    }

    for(int k = 1; k < 20; k ++){
        for(int i = 0; i < N; i ++){
            if(best[i][k-1] == -1){
                best[i][k] = -1;
            }else{
                best[i][k] = best[best[i][k-1]][k-1];
            }
        }
    }
}

int minimum_jumps(int A, int B, int C, int D){
    assert(0 <= A && A <= B && B < C && C <= D && D <= M-1);

    ii maxValCD = findMax(C, D);
    int maxIndxCD = prevGreater[maxValCD.second][0];
    //printf("maxValCD=%d\n", maxValCD);
    A = max(maxIndxCD+1, A);

    if(A > B){return -1;}

    ii maxValAB = findMax(A, B);
    int X = maxValAB.second;

    int cutOffIndx = X;
    for(int k = 19; k >= 0; k --){
        if(nextGreater[cutOffIndx][k] != M && nextGreater[cutOffIndx][k] < C){
            cutOffIndx = nextGreater[cutOffIndx][k];
        }
    }
    cutOffIndx = nextGreater[cutOffIndx][0];
    assert(cutOffIndx >= C && cutOffIndx <= D);

    int ans = 0;

    int X5 = X;
    int totalDist = 0;
    for(int k = 19; k >= 0; k --){
        int temp = best[X5][k];
        if(temp != -1 && A1[temp] < A1[cutOffIndx]){
            totalDist += (1<<k);
            X5 = temp;
        }
        assert(X5 != -1);
    }

    int X2 = X;
    totalDist = max(totalDist-2, 0);
    ans += totalDist;
    for(int k = 19; k >= 0; k --){
        int temp = best[X2][k];
        if(totalDist >= (1<<k)){
            totalDist -= (1<<k);
            X2 = temp;
        }
    }

    for(int k = 19; k >= 0; k --){
        int temp = nextGreater[X2][k];
        if(temp != M && temp < C){
            ans += (1<<k);
            X2 = temp;
        }
    }

    X2 = nextGreater[X2][0];
    ans ++;

    assert(X2 >= C && X2 <= D);

    while(X2 < C){
        int X3, X4;
        if(prevGreater[X2][0] == -1){
            X3 = nextGreater[X2][0];
            X4 = prevGreater[X2][0];
        }else if(nextGreater[X2][0] == M){
            X3 = prevGreater[X2][0];
            X4 = nextGreater[X2][0];
        }else if(A1[prevGreater[X2][0]] > A1[nextGreater[X2][0]]){
            X3 = prevGreater[X2][0];
            X4 = nextGreater[X2][0];
        }else{
            X3 = nextGreater[X2][0];
            X4 = prevGreater[X2][0];
        }

        assert(X3 >= 0 && X3 < M);

        //printf("X2=%d; X3=%d; X4=%d\n", X2, X3, X4);
        if(X4 >= C && X4 <= D){
            X2 = X4;
        }else if(A1[X3] > maxValCD.first){
            X2 = X4;
        }else{
            X2 = X3;
        }
        //printf("X2=%d\n", X2);
        ans ++;
        assert(X2 >= 0 && X2 < M);
    }

    return ans;
}

Compilation message

jumps.cpp: In function 'void init(int, std::vector<int>)':
jumps.cpp:109:17: warning: variable 'X4' set but not used [-Wunused-but-set-variable]
  109 |         int X3, X4;
      |                 ^~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 303 ms 66440 KB Output is correct
4 Correct 1840 ms 83344 KB Output is correct
5 Correct 1164 ms 42132 KB Output is correct
6 Correct 1585 ms 83376 KB Output is correct
7 Correct 1155 ms 57104 KB Output is correct
8 Correct 1582 ms 83324 KB Output is correct

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 1 ms 328 KB Output is correct
4 Correct 1 ms 328 KB Output is correct
5 Correct 2 ms 328 KB Output is correct
6 Incorrect 3 ms 328 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #3
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 1 ms 328 KB Output is correct
4 Correct 1 ms 328 KB Output is correct
5 Correct 2 ms 328 KB Output is correct
6 Incorrect 3 ms 328 KB Output isn't correct
7 Halted 0 ms 0 KB -

Subtask #4
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 1 ms 328 KB Output is correct
4 Correct 1 ms 328 KB Output is correct
5 Correct 182 ms 65688 KB Output is correct
6 Correct 230 ms 81692 KB Output is correct
7 Correct 106 ms 41896 KB Output is correct
8 Correct 255 ms 81584 KB Output is correct
9 Correct 18 ms 12524 KB Output is correct
10 Correct 234 ms 81728 KB Output is correct
11 Correct 234 ms 83376 KB Output is correct
12 Correct 229 ms 82944 KB Output is correct
13 Incorrect 247 ms 82912 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 1 ms 328 KB Output is correct
4 Incorrect 397 ms 37416 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #6
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 1 ms 328 KB Output is correct
4 Incorrect 397 ms 37416 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #7
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 328 KB Output is correct
2 Correct 1 ms 328 KB Output is correct
3 Correct 303 ms 66440 KB Output is correct
4 Correct 1840 ms 83344 KB Output is correct
5 Correct 1164 ms 42132 KB Output is correct
6 Correct 1585 ms 83376 KB Output is correct
7 Correct 1155 ms 57104 KB Output is correct
8 Correct 1582 ms 83324 KB Output is correct
9 Correct 1 ms 328 KB Output is correct
10 Correct 1 ms 328 KB Output is correct
11 Correct 1 ms 328 KB Output is correct
12 Correct 1 ms 328 KB Output is correct
13 Correct 2 ms 328 KB Output is correct
14 Incorrect 3 ms 328 KB Output isn't correct
15 Halted 0 ms 0 KB -