Class Solution
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
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Constructor Summary
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Method Summary
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
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Constructor Details
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Solution
public Solution()
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Method Details
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countPairs
public int countPairs(int[] d)
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