Convert the given BCD to its equivalent Binary form - GeeksforGeeks

11 Jun, 2021
Given a BCD (Binary Coded Decimal), the task is to convert this to its equivalent Binary number. Examples: 
Input: 1001000 Output: 110000 Explanation: Integer value of the given BCD is 48(0100 -> 4, 1000 -> 8). (48)10 = (110000)2Input: 1001001 Output: 110001 
Approach: In order to solve this problem we need to split the given BCD number into binary chunks of length 4 and convert them to integer one by one to generate the final integer representation of the given BCD. Once generated, convert the integer to its binary form.Below is the implementation of the above approach. 
C++
Java
Python3
C#
Javascript
// C++ code to convert BCD to its// equivalent Binary #include <bits/stdc++.h>using namespace std; // Function to convert BCD to Decimalstring bcdToBinary(string s){    int l = s.length();    int num = 0;    int mul = 1;    int sum = 0;          // If the length of given BCD is not    // divisible by 4    for (int i = l % 4 - 1; i >= 0; i--)    {        sum += (s[i] - '0') * mul;        mul *= 2;    }    num = sum;    sum = 0;    mul = pow(2, 3);    int ctr = 0;    for (int i = l % 4; i < l; i++)    {        ctr++;        sum += (s[i] - '0') * mul;        mul /= 2;        if (ctr == 4) {            num = num * 10 + sum;            sum = 0;            mul = pow(2, 3);            ctr = 0;        }    }     // Convert decimal to binary    string ans = "";    while (num > 0) {        ans += (char)(num % 2 + '0');        num /= 2;    }    reverse(ans.begin(), ans.end());    return ans;} // Driver Codeint main(){    string s = "1001000";     // Function Call    cout << bcdToBinary(s);    return 0;}
// Java code to convert BCD to its// equivalent Binaryimport java.io.*;import java.util.*; class GFG{     // Function to convert BCD to Decimalstatic String bcdToBinary(String s){    int l = s.length();    int num = 0;    int mul = 1;    int sum = 0;         // If the length of given BCD is not    // divisible by 4    for(int i = l % 4 - 1; i >= 0; i--)    {        sum += (s.charAt(i) - '0') * mul;        mul *= 2;    }     num = sum;    sum = 0;    mul = (int)Math.pow(2, 3);    int ctr = 0;         for(int i = l % 4; i < l; i++)    {        ctr++;        sum += (s.charAt(i) - '0') * mul;        mul /= 2;                 if (ctr == 4)        {            num = num * 10 + sum;            sum = 0;            mul = (int)Math.pow(2, 3);            ctr = 0;        }    }         // Convert decimal to binary    String ans = "";    while (num > 0)    {        ans += (char)(num % 2 + '0');        num /= 2;    }     StringBuilder ans1 = new StringBuilder();     // Append a string into StringBuilder input1    ans1.append(ans);     // Reverse StringBuilder input1    ans = ans1.reverse().toString();     return ans;} // Driver codepublic static void main(String[] args){    String s = "1001000";         // Function call    System.out.println(bcdToBinary(s));}} // This code is contributed by coder001
# Python3 code to convert# BCD to its equivalent Binary # Function to convert# BCD to Decimaldef bcdToBinary(s):     l = len(s)    num = 0;    mul = 1;    sum = 0;          # If the length of given    # BCD is not divisible by 4       for i in range(l % 4 - 1,                   -1, -1):           sum += (ord(s[i]) -                ord('0')) * mul;        mul *= 2;         num = sum;    sum = 0;    mul = pow(2, 3);    ctr = 0;         for i in range(l % 4, l):           ctr += 1;        sum += (ord(s[i]) -                ord('0')) * mul;        mul //= 2;        if (ctr == 4):            num = num * 10 + sum;            sum = 0;            mul = pow(2, 3);            ctr = 0;             # Convert decimal to binary    ans = "";    while (num > 0):        ans += (chr((num % 2) +                ord('0')));        num //= 2;    ans = ans[:: -1]         return ans; # Driver codeif __name__ == "__main__":         s = "1001000";      # Function Call    print(bcdToBinary(s)); # This code is contributed by rutvik_56
// C# code to convert BCD to its// equivalent Binaryusing System;using System.Text;public class GFG{      // Function to convert BCD to Decimalstatic String bcdToBinary(String s){    int l = s.Length;    int num = 0;    int mul = 1;    int sum = 0;          // If the length of given BCD is not    // divisible by 4    for(int i = l % 4 - 1; i >= 0; i--)    {        sum += (s[i] - '0') * mul;        mul *= 2;    }    num = sum;    sum = 0;    mul = (int)Math.Pow(2, 3);    int ctr = 0;    for(int i = l % 4; i < l; i++)    {        ctr++;        sum += (s[i] - '0') * mul;        mul /= 2;        if (ctr == 4)        {            num = num * 10 + sum;            sum = 0;            mul = (int)Math.Pow(2, 3);            ctr = 0;        }    }          // Convert decimal to binary    String ans = "";    while (num > 0)    {        ans += (char)(num % 2 + '0');        num /= 2;    }    StringBuilder ans1 = new StringBuilder();      // Append a string into StringBuilder input1    ans1.Append(ans);      // Reverse StringBuilder input1    ans = reverse(ans1.ToString());    return ans;}static String reverse(String input){        char[] a = input.ToCharArray();        int l, r = a.Length - 1;        for (l = 0; l < r; l++, r--)        {            char temp = a[l];            a[l] = a[r];            a[r] = temp;        }        return String.Join("",a);    }   // Driver codepublic static void Main(String[] args){    String s = "1001000";          // Function call    Console.WriteLine(bcdToBinary(s));}} // This code is contributed by shikhasingrajput
<script>// Javascript code to convert BCD to its// equivalent Binary // Function to convert BCD to Decimalfunction bcdToBinary(s){    let l = s.length;    let num = 0;    let mul = 1;    let sum = 0;     // If the length of given BCD is not    // divisible by 4    for (let i = l % 4 - 1; i >= 0; i--)    {        sum += (s[i].charCodeAt(0) - '0'.charCodeAt(0)) * mul;        mul *= 2;    }    num = sum;    sum = 0;    mul = Math.pow(2, 3);    let ctr = 0;    for (let i = l % 4; i < l; i++) {        ctr++;        sum += (s[i].charCodeAt(0) - '0'.charCodeAt(0)) * mul;        mul = Math.floor(mul / 2);        if (ctr == 4) {            num = num * 10 + sum;            sum = 0;            mul = Math.pow(2, 3);            ctr = 0;        }    }     // Convert decimal to binary    let ans = "";    while (num > 0) {        ans += String.fromCharCode(num % 2 + '0'.charCodeAt(0));        num = Math.floor(num / 2);    }    ans = ans.split("").reverse().join("")    console.log(ans)    return ans;} // Driver Codelet s = "1001000"; // Function Calldocument.write(bcdToBinary(s)); // This code is contributed by _saurabh_jaiswal</script>
110000
 
Time Complexity: O(N) where N denotes the length of the BCD string provided Auxiliary Space: O(1)
coder001
shikhasingrajput
rutvik_56
_saurabh_jaiswal
base-conversion
Bit Magic
Mathematical
Mathematical
Bit Magic
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.
Comments
Old Comments
Set, Clear and Toggle a given bit of a number in C
Check whether K-th bit is set or not
Write an Efficient Method to Check if a Number is Multiple of 3
Reverse actual bits of the given number
Program to find parity
Program for Fibonacci numbers
Write a program to print all permutations of a given string
C++ Data Types
Set in C++ Standard Template Library (STL)
Coin Change | DP-7