# Decimal to Binary (INTRN004) : Solution with hints

Problem

Hint 1:

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To go from binary to decimal, we use the following procedure.

we take the right-most digit, and multiply by 1, and add to res.

Then we take second-right most digit, and multiply by 2, and add to res.

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We take i^{\texttt{th}} from the right, and multiply it by 2^{i - 1} and add res.

We want to reverse this process.

Try writing the number 5 in binary.

Hint 2:

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When we take N \bmod 2, we get the remainder when N is divided by 2.

What happens when we divide N by 2 (integer division)?

Write 9 in binary, then divide it by 2, and write the result in binary.
Then divide that number by 2, and write the result in binary.

Hint 3:

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Dividing by 2 chops off the right-most digit in the binary representation.

Hint 4:

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How long do we need to do this process to get all the digits in the binary representation of N?

Hint 5:

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Keep dividing by 2 until you reach 0.

Hint 6:

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In what order do we get the binary digits via this process?
Try with examples 9 and 8.

Hint 7:

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Reverse order.

Hint 8:

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We can store the individual binary digits in a list and print it in reverse order.

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