Checking if an index has been used

I am to create a function called "anagram" that will receive an input string, shuffle the letters, and return an output string of the randomly arranged characters. Specifically, right now, I have to use a for loop that generates a random index of the input string, with an if statement that will check if the index has been used already to avoid repetition (I asked a question about this earlier but now I'm more clear on the requirements).

I'm just confused as to how to iterate through the output vector that's being created, to see if the index has been used already. I'm thinking an if statement, but what should my condition be, to run through the index and see if it's in there?

Answer 1

[John D'Errico]

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