#2523
Closest Prime Numbers in Range
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Description
Given two positive integers left and right, find the two integers num1 and num2 such that:
- left <= num1 < num2 <= right .
- Both num1 and num2 are prime numbers.
- num2 - num1 is the minimum amongst all other pairs satisfying the above conditions.
Return the positive integer array ans = [num1, num2]. If there are multiple pairs satisfying these conditions, return the one with the smallest num1 value. If no such numbers exist, return [-1, -1].
Example 1:
Input: left = 10, right = 19
Output: [11,13]
Explanation: The prime numbers between 10 and 19 are 11, 13, 17, and 19.
The closest gap between any pair is 2, which can be achieved by [11,13] or [17,19].
Since 11 is smaller than 17, we return the first pair.
Example 2:
Input: left = 4, right = 6
Output: [-1,-1]
Explanation: There exists only one prime number in the given range, so the conditions cannot be satisfied.
Solution