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Problem · Array

Happy Neighborhood

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Problem statement

In a neighborhood, there are N empty houses numbered from 1 to N arranged in a line. Each day, starting from day 1, one house will be occupied by residents. The sequence of occupied houses is given as a permutation of length N. On the ith day, the house with the number given by the ith element of the permutation will be occupied.

The neighborhood will be considered happy if there is at least one set of consecutive occupied houses. On which day will the neighborhood become happy?

Note: A permutation of length N is an array of N integers where each element is between 1 and N, with no repetitions.

Function

googleHappyNeighbor(N: int, M: int, house: int[]) → int

Complete the function solve. This function takes the following 3 parameters and returns the required answer:

  • N: Represents the number of houses
  • M: Represents the number of consecutive houses needed
  • house: Represents an array indicating the house that will be filled on each day

    • Input format for custom testing

    Note: Use this input format if you are testing against custom input or writing code in a language where we don't provide boilerplate code.

  • The first line contains N denoting the number of houses.
  • The second line contains M denoting the number of consecutive houses needed.
  • The third line contains an array house denoting the house that will be filled on each day.

    • Output format

    Print a single integer representing the first day on which the neighborhood becomes happy.

    Examples

    Example 1

    N = 3M = 1house = [3, 2, 1]return = 1
    tomtom's note: Not entirely sure about the explanation O.o Since the requirement is for at least one set of consecutive occupied houses and the first house to be occupied is house number 3, the neighborhood becomes happy on day 1.

    Constraints

    • 1 ≤ M ≤ N ≤ 2 * 10^5
    • house.length = N
    • house is a permutation of the integers from 1 through N.

    More Google problems

    drafts saved locally
    public int googleHappyNeighbor(int N, int M, int[] house) {
  // write your code here
}
    N3
    M1
    house[3, 2, 1]
    expected1
    checking account