Given an octal number as input. Now, write a Kotlin program to convert Octal number to Binary.

Input:
7

Output:
111

Input:
120

Output:
001010000

Input:
121

Output:
001010001

1. Program to Convert Octal to Binary

Pseudo Algorithm

• Initialize a variable binaryNum with empty string.
• Now, convert each digit of octal number into binary and append it to binaryNum.
• Repeat till last digit of the octal number.
• Finally, binaryNum will contain binary representation of octal number.

Sourcecode –

fun main() {

    println("Enter n:")
    val octalN = readLine()

    if(checkOctalNumber(octalN!!)) {
        val octalNumString: String = octalN

        var i = 0
        var binaryNum = ""
        while(i < octalNumString.length) {
            when(octalNumString[i]) {
                '0'  -> binaryNum += "000"
                '1'  -> binaryNum += "001"
                '2'  -> binaryNum += "010"
                '3'  -> binaryNum += "011"
                '4'  -> binaryNum += "100"
                '5'  -> binaryNum += "101"
                '6'  -> binaryNum += "110"
                '7'  -> binaryNum += "111"
            }
            i++
        }
        println("Equivalent Binary : $binaryNum")
    } else {
        println("$octalN is not an octal number")
    }
}

private fun checkOctalNumber(octalNum: String): Boolean {
    var isOctal = true

    for(charAtPos in octalNum) {
        if(!((charAtPos >= '0') && (charAtPos <= '7'))) {
            isOctal = false
            break
        }
    }
    return isOctal
}

When you run the program, output will be –

Enter n:
7657576576575
Equivalent Binary : 111110101111101111110101111110101111101

Explanation:

We just extract each digit from the original octal number. Then, we converted that digit into binary and appended it with binaryNum
variable. Finally, binaryNum contains binary representation of the octal number.

Thus, we went through Kotlin Program to Convert Octal number to Binary number.