PR Title Format: 176.NthHighestSalary.cpp

Intuition

The problem asks to find the Nth highest salary from the Employee table. A direct approach is to use SQL concepts like ORDER BY with LIMIT and OFFSET, but in LeetCode-style C++ SQL implementation, we use a subquery to skip the top (N-1) distinct salaries and then select the next highest.

The key idea is:

Sort distinct salaries in descending order.

Skip the first (N-1) salaries.

Return the next one.

Approach

We use an SQL query wrapped in a C++ function:

The inner query selects all distinct salaries in descending order.

The LIMIT 1 OFFSET N-1 ensures we fetch the Nth highest.

If N is greater than the number of distinct salaries, we return NULL.

In LeetCode’s context, the function must return a query string.

Code Solution (C++)
// 176.NthHighestSalary.cpp

class Solution {
public:
string nthHighestSalary(int N) {
return "SELECT DISTINCT Salary FROM Employee ORDER BY Salary DESC LIMIT 1 OFFSET " + to_string(N - 1);
}
};

Related Issues

Closes SjxSubham#176

By submitting this PR, I confirm that:

This is my original work not totally AI generated

I have tested the solution thoroughly on LeetCode

I have maintained proper PR description format

This is a meaningful contribution, not spam