# Program to convert decimal to binary in C++

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Given a decimal number, we have to write a program to calculate its binary equivalent.

**# Approaching the problem**

To calculate binary equivalent of any decimal number, we divide it by 2 and store the remainder till the number becomes either 1 or 0 and then we write all the remainder in the opposite order of how they were obtained.

2 | 13 | 1 |

2 | 6 | 0 |

2 | 3 | 1 |

1 |

1310=11012

To implement this, we will initialize an array to store the remainder and keep dividing the number by 2, Then we will print the array in the reverse order.

**# Algorithm**

- Input the decimal number and store it in
*dec*. - Initialize an array
*bin*of size 16 (binary equivalent of -32768 has 16 digits which is the max limit of int). - Divide
*dec*by 2 and store the remainder in the array. - Set
*dec*to the quotient. - Repeat the above two steps till the number is greater than zero.
- Print the array in the reverse order and that is the binary equivalent.

**Code**

```
#include <iostream>
using namespace std;
int main()
{
int dec, bin[16], i = 0, j = 0; //dec and bin to store number and ints binary equivalent and i&j are for index maintaining
cout << "Enter a decimal number\n";
cin >> dec;
while (dec > 0) //calculating the binary equivalent and storing it in the array
{
bin[i] = dec % 2;
dec = dec / 2;
++i;
}
cout << "Binary Equivalent:"; //printing the array in reverse order
for (j = i - 1; j >= 0; --j)
cout << bin[j];
return 0;
}
```

**Output**

```
Enter a decimal number
5
Binary Equivalent:101
```