LeetCode 0177. Nth Highest Salary Solution in Java, Python, C++, JavaScript, Go & Rust | Explanation + Code

Description

Table: Employee

+-------------+------+
| Column Name | Type |
+-------------+------+
| id          | int  |
| salary      | int  |
+-------------+------+
id is the primary key (column with unique values) for this table.
Each row of this table contains information about the salary of an employee.

 

Write a solution to find the nth highest distinct salary from the Employee table. If there are less than n distinct salaries, return null.

The result format is in the following example.

 

Example 1:

Input: 
Employee table:
+----+--------+
| id | salary |
+----+--------+
| 1  | 100    |
| 2  | 200    |
| 3  | 300    |
+----+--------+
n = 2
Output: 
+------------------------+
| getNthHighestSalary(2) |
+------------------------+
| 200                    |
+------------------------+

Example 2:

Input: 
Employee table:
+----+--------+
| id | salary |
+----+--------+
| 1  | 100    |
+----+--------+
n = 2
Output: 
+------------------------+
| getNthHighestSalary(2) |
+------------------------+
| null                   |
+------------------------+

Solutions

Solution 1

Pythonsql

import pandas as pd def nth_highest_salary(employee: pd.DataFrame, N: int) -> pd.DataFrame: if N < 1: return pd.DataFrame({"getNthHighestSalary(" + str(N) + ")": [None]}) unique_salaries = employee.salary.unique() if len(unique_salaries) < N: return pd.DataFrame([np.NaN], columns=[f"getNthHighestSalary({N})"]) else: salary = sorted(unique_salaries, reverse=True)[N - 1] return pd.DataFrame([salary], columns=[f"getNthHighestSalary({N})"])(code-box)

CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT BEGIN SET N = N - 1; RETURN ( # Write your MySQL query statement below. SELECT ( SELECT DISTINCT salary FROM Employee ORDER BY salary DESC LIMIT 1 OFFSET N ) ); END(code-box)