Package g1401_1500.s1420_build_array_where_you_can_find_the_maximum_exactly_k_comparisons

Class Solution

java.lang.Object
g1401_1500.s1420_build_array_where_you_can_find_the_maximum_exactly_k_comparisons.Solution
public class Solution extends java.lang.Object
1420 - Build Array Where You Can Find The Maximum Exactly K Comparisons.

Hard

You are given three integers n, m and k. Consider the following algorithm to find the maximum element of an array of positive integers:

You should build the array arr which has the following properties:

  • arr has exactly n integers.
  • 1 <= arr[i] <= m where (0 <= i < n).
  • After applying the mentioned algorithm to arr, the value search_cost is equal to k.

Return the number of ways to build the array arr under the mentioned conditions. As the answer may grow large, the answer must be computed modulo 109 + 7.

Example 1:

Input: n = 2, m = 3, k = 1

Output: 6

Explanation: The possible arrays are [1, 1], [2, 1], [2, 2], [3, 1], [3, 2] [3, 3]

Example 2:

Input: n = 5, m = 2, k = 3

Output: 0

Explanation: There are no possible arrays that satisify the mentioned conditions.

Example 3:

Input: n = 9, m = 1, k = 1

Output: 1

Explanation: The only possible array is [1, 1, 1, 1, 1, 1, 1, 1, 1]

Constraints:

  • 1 <= n <= 50
  • 1 <= m <= 100
  • 0 <= k <= n

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    numOfArrays(int n, int m, int k)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • numOfArrays

      public int numOfArrays(int n, int m, int k)