# Find the Duplicate Number Leetcode Solution

Hello coders, Today I am going to solve another Leetcode problem titled ” Find the Duplicate Number Leetcode Solution “. As we know any number which appears more than once is known as a duplicate number.

Let’s see the complete problem statement :

## Problem statement:

Given an array of integers `nums` containing `n + 1` integers where each integer is in the range `[1, n]` inclusive.

There is only one repeated number in `nums`, return this repeated number.

You must solve the problem without modifying the array `nums` and uses only constant extra space.

Example 1:

```Input: nums = [1,3,4,2,2]
Output: 2
Explanation: Here, we can clearly see 2 appears two times. Hence the output will be 2.
```

Example 2:

```Input: nums = [3,1,3,4,2]
Output: 3
Explanation: Here, 3 appears two times and the output will be 3.

```

## Find the Duplicate Number Leetcode Solution in Python

```#Find the Duplicate Number Leetcode Solution in Python

class Solution:
def findDuplicate(self, nums: List[int]) -> int:

low = 1
high = len(nums) - 1

while low <= high:
cur = (low + high) // 2
count = 0

# Count how many numbers are less than or equal to 'cur'
count = sum(num <= cur for num in nums)
if count > cur:
dup = cur
high = cur - 1
else:
low = cur + 1

return dup

#Find the Duplicate Number Leetcode Solution in Python```

Disclaimer: This problem(Find the Duplicate Number Leetcode solution) is originally created by LeetcodeCodesagar only provides a solution for it. This solution is only for Educational and learning purposes.