Class Solution


  • public class Solution
    extends Object
    1711 - Count Good Meals.

    Medium

    A good meal is a meal that contains exactly two different food items with a sum of deliciousness equal to a power of two.

    You can pick any two different foods to make a good meal.

    Given an array of integers deliciousness where deliciousness[i] is the deliciousness of the ith item of food, return the number of different good meals you can make from this list modulo 109 + 7.

    Note that items with different indices are considered different even if they have the same deliciousness value.

    Example 1:

    Input: deliciousness = [1,3,5,7,9]

    Output: 4

    Explanation: The good meals are (1,3), (1,7), (3,5) and, (7,9). Their respective sums are 4, 8, 8, and 16, all of which are powers of 2.

    Example 2:

    Input: deliciousness = [1,1,1,3,3,3,7]

    Output: 15

    Explanation: The good meals are (1,1) with 3 ways, (1,3) with 9 ways, and (1,7) with 3 ways.

    Constraints:

    • 1 <= deliciousness.length <= 105
    • 0 <= deliciousness[i] <= 220
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • countPairs

        public int countPairs​(int[] d)