How to switch between a binary number as String and a as a list of digits?

I was trying with String Functions and I viewing any posts and have no results

I want to know

1.- From

cromo33 = Table[RandomInteger[], {i, 1, 33}]
cromo33

that gives {1,0,1,1,1,0,1,......,1,0,0} , alist of 33 elements

How can you obtain "1011101.....100" ?

2.- From

IntegerString[RandomInteger[8], 2] // InputForm

that gives 101 (a little add-on... ¿how can I force this to obtain 4 digits in any random number?)

How can you obtain a list {1,0,1} ?

Answer

There are built-in functions to play:

NumberForm[FromDigits@RandomInteger[1, 5], 6, NumberPadding -> "0"]

"0011101"

Or very straightforward approach:

1

RandomInteger[1, 5]
PadLeft[%, 7]
ToString /@ %
StringJoin@%

{0, 1, 0, 1, 0}
{0, 0, 0, 1, 0, 1, 0}

{"0", "0", "0", "1", "0", "1", "0"}
"0001010"

2

IntegerString[RandomInteger[8], 2]
Characters@%
PadLeft[%, 4]
ToExpression@%

"101"
{"1", "0", "1"}
{0, "1", "0", "1"}
{0, 1, 0, 1}

Comments

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