$3.$ a$)$ Write a non$-$recursive function $\backslash (\backslash$operatorname$\{$dec$\}2\backslash$operatorname$\{$bin$\}()\backslash )$ that takes a positive decimal integer $\backslash (\backslash$boldsymbol$\{$n$\}\backslash )$ as input and returns a string shown the binary representation of the number. NOTE: You are not allowed to use any built$-$in functions for converting from decimal to binary.

b$)$ Randomly generate an integer between $1000$ and $5000$ and assign it to a variable num. Display the value of num, then call $\backslash (\backslash$operatorname$\{$dec$\}2$ b i n$()\backslash )$ with num as input and display the result.

Sample outputs: