How to perform a byte-wise XOR of a string with a hex value in C++?

Question

Let's say I have the string string str = "this is a string";

and a hexadecimal value int value = 0xbb;

How would I go about performing a byte-wise XOR of the string with the hex value in C++?

Answer 1

Just iterate through the string and XOR each character:

for (size_t i = 0; i < str.size(); ++i)
    str[i] ^= 0xbb;

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or perhaps more idiomatically in C++11 and later:

for (char &c : str)
    c ^= 0xbb;

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See also this question.