﻿ Java - Add one to the number of positive numbers in an array

# Java: Plus one to the number of a specified positive numbers represented as an array of digits

## Java Basic: Exercise-179 with Solution

Write a Java program to add one to a positive number represented as an array of digits.

Sample array: [9, 9, 9, 9] which represents 9999
Output: [1, 0, 0, 0, 0].

Sample Solution:

Java Code:

``````// Importing necessary Java utilities
import java.util.*;

// Main class Solution
public class Solution {
// Main method
public static void main(String[] args) {
// Initializing an array of integers
int[] nums = {9, 9, 9, 9};

// Printing the original array
System.out.println("Original array: " + Arrays.toString(nums));

// Printing the array of digits after adding one to the input array
System.out.println("Array of digits: " + Arrays.toString(plus_One_digit(nums)));
}

// Method to add one to the last digit of the input array
public static int[] plus_One_digit(int[] digits_nums) {
// Looping through the array from the end to the start
for (int i = digits_nums.length - 1; i > -1; --i) {
// Checking if the digit is not 9
if (digits_nums[i] != 9) {
digits_nums[i] += 1; // Incrementing the digit by 1

// Setting the digits after the incremented digit to 0
for (int j = i + 1; j < digits_nums.length; ++j) {
digits_nums[j] = 0;
}

return digits_nums; // Returning the updated array
}
}

// If all digits are 9, creating a new array with an additional digit for carrying over 1
int[] result = new int[digits_nums.length + 1];
result[0] = 1; // Setting the first digit to 1

return result; // Returning the new array with the carried over 1
}
}
```
```

Sample Output:

```Original array: [9, 9, 9, 9]
Array of digits: [1, 0, 0, 0, 0]
```

Flowchart:

Java Code Editor:

Contribute your code and comments through Disqus.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.

﻿