## Reverse a Number in PHP with Program

### This blog explains about Reverse a Number in PHP with Program . They are explained very well below :

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Hi,

Today, we will learn how to Reverse a Number in PHP with Program .

First consider the number 1234.

Here we need to get last number first.

Hence i am using the modulus operator with divisor value  as 10  for getting the remainder value to move from last into first place.

Shall we go through the program to reverse a number in PHP now?

# Reverse String

A string can be reversed either using strrev() function or simple PHP code.

For example, on reversing JAVATPOINT it will become TNIOPTAVAJ.

## Logic:

• Assign the string to a variable.
• Calculate length of the string.
• Declare variable to hold reverse string.
• Run for loop.
• Concatenate string inside for loop.
• Display reversed string
• Take (input or assign) a number
• Assign 0 to the variable, in which we are going to store reverse number (Here, I am using ‘reverse’)
• Run the following two steps until number is not zero
• Get the digit using modules (%) operator and add it into the ‘reverse*10’
• Now, divide the number by 10Finally, when number will be zero, print the ‘reverse’

# Swapping two numbers

Two numbers can be swapped or interchanged. It means first number will become second and second number will become first.

For example

1. a = 20, b = 30
2. After swapping,
3. a = 30, b = 20

There are two methods for swapping:

• By using third variable.
• Without using third variable.

## II . Swapping Without using Third Variable

Swap two numbers without using a third variable can be  done in two ways:

• Using arithmetic operation + and ?
• Using arithmetic operation * and /

### `<?php` `\$m = 1234; \$r=0;` `for(\$i=0; \$i<3; \$i++)` `{ ` ` \$r=\$m%10;` ` echo \$r;` ` \$m = \$m/10;` `}` `\$m=\$m%10;` `echo \$m;` `?>`

Output:

4321

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### REFERENCES :

https://www.javatpoint.com/php-fibonacci-series