Dear all,

I have a whole bunch (~66k) strings that are long (~400k characters). For all strings the same smallish number of columns need to be removed before the result is printed. So basically:

string1 = 0121012102??????????12121212????????
string2 = 0111011102??????????12111112????????
string3 = 0111011102??????????12111112????????

mask = 0001111111001111001111111 (etc.)

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...and now only print out the characters in the strings that correspond with 1 in the mask, omitting the ones that have 0. I've tried doing this by splitting the strings and then taking array slices, but this is way too slow. I suspect there is some clever way if doing this with bitwise operators but I'm still confused how it works after reading the relevant PODs. Anyone have any suggestions?

Thanks!

In reply to using bits to print part of a string by Anonymous Monk

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