How to Increment by 1 to all the Digits of a given Integer in PHP ?

In PHP, incrementing all digits of an integer by 1 involves breaking the number into individual digits, adding 1 to each, and reconstructing the integer. This can be accomplished through array manipulation, arithmetic operations, or string conversion methods. Suppose, if the given number is 123 then the desired output is 234.

Examples:

Input: 12345
Output: 23456
Input: 110102
Output: 221213

Using String Conversion

Generate a string which will be of the same length as the input integer and will contain only 1’s in it. Then we will convert this string into an integer. Then, finally add this integer to the original integer to get the desired result.

Example: Illustration of incrementing by 1 to all the digits of a given integer in PHP using string conversion method.

PHP

<?php

// Declaring the number
$number = 110102;
echo "Original Number: $number \n";

// Number of digits in the number
$len = strlen((string) $number);

// Generating the addition string
$add = str_repeat("1", $len);

// Converting it to an integer
$str_num = (int) $add;

// Adding them and displaying the result
$result = $number + $str_num;

// Print the result
echo "Incremented Number: $result";
?>

Output

Original Number: 110102 
Incremented Number: 221213

Using Arithmetic Operations

Take an integer with value 1. Then we will perform arithmetic operations on it to get an integer of only 1s which will be of same length as that or original integer. Then, finally we will add this integer to original integer to get the desired result.

Example: Illustration of incrementing by 1 to all the digits of a given integer in PHP using arithmetic operations.

PHP

<?php

// Declaring the number
$number = 1920;
echo "Original Number: $number \n";

// Number of digits in the number
$len = strlen((string) $number);
// Declaring another variable with value 1
$add = 1;

for ($i = 0; $i < $len; $i++) {

    // Adding variable $add and $number
    $number = $number + $add;

    // Multiplying the value of $add with 10
    $add = $add * 10;
}
// Printing the result
echo "Incremented Number: $number";
?>

Output

Original Number: 1920 
Incremented Number: 3031

Using Array Manipulation

Create an array with value of all elements equals to 1. Then, merge all elements of array together into a string and then convert this string into a number. Finally, add this number to the original given integer to get the result.

Example: Illustration of incrementing by 1 to all the digits of a given integer in PHP using array manipulation method.

PHP

<?php

// Declaring the number
$number = 2024;
echo "Original Number: $number \n";

// Converting the number to an array of digits
$num_arr = str_split(strval($number));

// Counting the number of elements n numberArray
$len = count($num_arr);

// Creating an array of 1s with the length = len
$ones_arr = array_fill(0, $len, 1);

// Joining all array elements to form a string of 1s
// with length len and then convert it to an integer
$str_num = (int) implode("", $ones_arr);

// Adding them and displaying the result
$result = $number + $str_num;

// Print the result
echo "Incremented Number: $result";
?>

Output

Original Number: 2024 
Incremented Number: 3135