Description:
Given an integer array nums, return the third distinct maximum number in this array. If the third maximum does not exist, return the maximum number.
Examples:
Example 1:
Input: nums = [3,2,1]
Output: 1
Explanation:
The first distinct maximum is 3.
The second distinct maximum is 2.
The third distinct maximum is 1.
Example 2:
Input: nums = [1,2]
Output: 2
Explanation:
The first distinct maximum is 2.
The second distinct maximum is 1.
The third distinct maximum does not exist, so the maximum (2) is returned instead.
Example 3:
Input: nums = [2,2,3,1]
Output: 1
Explanation:
The first distinct maximum is 3.
The second distinct maximum is 2 (both 2's are counted together since they have the same value).
The third distinct maximum is 1.Solution in Python:
- Remove Duplicates: First, we need to remove duplicate values from the array to ensure we only work with distinct values.
- Sort the Array: Sort the array in descending order.
- Check the Length: Check if the length of the resulting array is at least 3. If it is, return the third maximum value. If not, return the maximum value.
Python
class Solution:
def thirdMax(self, nums: List[int]) -> int:
# Step 1: Remove duplicates by converting the list to a set
nums = list(set(nums))
# Step 2: Sort the list in descending order
nums.sort(reverse=True)
# Step 3: Check if there are at least 3 distinct numbers
if len(nums) >= 3:
# Return the third distinct maximum number
return nums[2]
else:
# Return the maximum number (first element in the sorted list)
return nums[0]Solution in Javascript:
JavaScript
/**
* @param {number[]} nums
* @return {number}
*/
var thirdMax = function(nums) {
// Step 1: Remove duplicates by converting the array to a Set and back to an array
nums = [...new Set(nums)];
// Step 2: Sort the array in descending order
nums.sort((a, b) => b - a);
// Step 3: Check if there are at least 3 distinct numbers
if (nums.length >= 3) {
// Return the third distinct maximum number
return nums[2];
} else {
// Return the maximum number (first element in the sorted array)
return nums[0];
}
};Solution in Java:
Java
import java.util.*;
class Solution {
public int thirdMax(int[] nums) {
// Step 1: Use a HashSet to remove duplicates
Set<Integer> set = new HashSet<>();
for (int num : nums) {
set.add(num);
}
// Step 2: Convert the set to a list and sort it in descending order
List<Integer> sortedList = new ArrayList<>(set);
Collections.sort(sortedList, Collections.reverseOrder());
// Step 3: Check if there are at least 3 distinct numbers
if (sortedList.size() >= 3) {
// Return the third distinct maximum number
return sortedList.get(2);
} else {
// Return the maximum number (first element in the sorted list)
return sortedList.get(0);
}
}
}Solution in C#:
C#
using System;
using System.Collections.Generic;
public class Solution {
public int ThirdMax(int[] nums) {
// Step 1: Use a HashSet to remove duplicates
HashSet<int> set = new HashSet<int>(nums);
// Step 2: Convert the set to a list and sort it in descending order
List<int> sortedList = new List<int>(set);
sortedList.Sort((a, b) => b.CompareTo(a));
// Step 3: Check if there are at least 3 distinct numbers
if (sortedList.Count >= 3) {
// Return the third distinct maximum number
return sortedList[2];
} else {
// Return the maximum number (first element in the sorted list)
return sortedList[0];
}
}
}