CODEWITHSUNDEEP
python
rhjs
rhjs

Reputation: 231

Is this a correct interpretation of Python code?

Here'a snippet of Python code:

 while i > 1:
    i = i - 1
    j = randrange(i)  # 0 <= j <= i-1
    items[j], items[i] = items[i], items[j]
 return

I want to use this algorithm in my Pascal project. The first 3 lines are absolutely clear to me, but what does this program do in the fourth line of code? Does it assign the random value kept on the j to the ith slot in the array, and then moves to the left (keeping the "used" values on the right)?

Upvotes: 0

Views: 55

Answers (1)

Tom Rees
Tom Rees

Reputation: 671

Python has a neat syntax for swapping variables:

a,b = b,a

Now a has the value of b and vice-versa. The fourth line of your program does exactly this.

Upvotes: 1

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