Problem
Return the second largest distinct value in the list. Repeated values count once.
Implement second_largest(numbers).
Input
numbers: A list of non-negative integers.
Output
Return the second largest distinct value, or -1 if it doesn't exist.
Constraints
0 ≤ length ≤ 100,000; 0 ≤ each value ≤ 10⁹
Examples
Example 1
Input:
numbers = [4, 9, 7, 9]
Expected output:
expected = 7
Input:
std::vector<long long> numbers = {4, 9, 7, 9};
Expected output:
long long expected = 7;
Input:
long[] numbers = new long[] {4, 9, 7, 9};
Expected output:
long expected = 7;
Explanation
Distinct values are 9, 7, 4; the second largest is 7.
Example 2
Input:
numbers = [5, 5]
Expected output:
expected = -1
Input:
std::vector<long long> numbers = {5, 5};
Expected output:
long long expected = -1;
Input:
long[] numbers = new long[] {5, 5};
Expected output:
long expected = -1;
Explanation
Only one distinct value exists, so the answer is -1.
References
This challenge is adapted for CodeUtility. Follow the statement and constraints above.