Package g1401_1500.s1434_number_of_ways_to_wear_different_hats_to_each_other

Class Solution

  • public class Solution
extends Object
    1434 - Number of Ways to Wear Different Hats to Each Other.

    Hard

    There are n people and 40 types of hats labeled from 1 to 40.

    Given a 2D integer array hats, where hats[i] is a list of all hats preferred by the ith person.

    Return the number of ways that the n people wear different hats to each other.

    Since the answer may be too large, return it modulo 109 + 7.

    Example 1:

    Input: hats = [[3,4],[4,5],[5]]

    Output: 1

    Explanation: There is only one way to choose hats given the conditions. First person choose hat 3, Second person choose hat 4 and last one hat 5.

    Example 2:

    Input: hats = [[3,5,1],[3,5]]

    Output: 4

    Explanation: There are 4 ways to choose hats: (3,5), (5,3), (1,3) and (1,5)

    Example 3:

    Input: hats = [[1,2,3,4],[1,2,3,4],[1,2,3,4],[1,2,3,4]]

    Output: 24

    Explanation: Each person can choose hats labeled from 1 to 4. Number of Permutations of (1,2,3,4) = 24.

    Constraints:

    • n == hats.length
    • 1 <= n <= 10
    • 1 <= hats[i].length <= 40
    • 1 <= hats[i][j] <= 40
    • hats[i] contains a list of unique integers.

    • Constructor Detail

      • Solution

        public Solution()