Given an array containing numbers from 1 to N, with one number missing, find the missing number

You can find the missing number in an array containing numbers from 1 to N (with one number missing) by calculating the sum of the first N natural numbers and then subtracting the sum of the given array. The difference will be the missing number. Here's a Python function to accomplish this:

        
            def find_missing_number(arr, N):
                expected_sum = N * (N + 1) // 2
                actual_sum = sum(arr)
                missing_number = expected_sum - actual_sum
                return missing_number
        
            # Example usage:
            arr = [1, 2, 4, 6, 3, 7, 8]
            N = len(arr) + 1  # N is the size of the original array + 1
            result = find_missing_number(arr, N)
            print("Missing number:", result)        
        
    

In this example, the find_missing_number function takes the array arr and the size N as parameters. It calculates the expected sum of the first N natural numbers using the formula N * (N + 1) // 2 and then subtracts the sum of the given array to find the missing number.

SSH (Secure Shell) is a cryptographic network protocol that allows secure communication between two computers over an insecure network. It is commonly used for remote login and command execution but can also be used for secure file transfer and other …

Setting up an Ubuntu Server on a DigitalOcean Droplet is a common task for deploying web applications, hosting websites, running databases, and more. Here's a detailed guide to help you through the process. Setting up an Ubuntu server on a DigitalOce …