# How to Write a program in c to convert decimal to binary

Decimal to binary conversion in c programming language. C source code for decimal to binary conversion:

Algorithm:

Binary number system: It is base 2 number system which uses the digits from 0 and 1.

Decimal number system:

It is base 10 number system which uses the digits from 0 to 9

Convert from decimal to binary algorithm:

Following steps describe how to convert decimal to binary

Step 1: Divide the original decimal number by 2
Step 2: Divide the quotient by 2
Step 3: Repeat the step 2 until we get quotient equal to zero.

Equivalent binary number would be remainders of each step in the reverse order.

Decimal to binary conversion with example:

For example we want to convert decimal number 25 in the binary.

Step 1: 25 / 2 Remainder : 1 , Quotient : 12
Step 2: 12 / 2 Remainder : 0 , Quotient : 6
Step 3: 6 / 2 Remainder : 0 , Quotient : 3
Step 4: 3 / 2 Remainder : 1 , Quotient : 1
Step 5: 1 / 2 Remainder : 1 , Quotient : 0

So equivalent binary number is: 11001
That is (25)10 = (11001)2

#include<stdio.h>
int main(){
long int decimalNumber,remainder,quotient;
int binaryNumber[100],i=1,j;
printf(“Enter any decimal number: “);
scanf(“%ld”,&decimalNumber);
quotient = decimalNumber;
while(quotient!=0){
binaryNumber[i++]= quotient % 2;
quotient = quotient / 2;
}
printf(“Equivalent binary value of decimal number %d: “,decimalNumber);
for(j = i -1 ;j> 0;j–)
printf(“%d”,binaryNumber[j]);
return 0;
}
Sample output:
Enter any decimal number: 50
Equivalent binary value of decimal number 50: 110010