printf slows down my program

Question

I have a small C program to calculate hashes (for hash tables). The code looks quite clean I hope, but there\'s something unrelated to it that\'s bugging me.

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Answer 1

If you are printf()ing to the console it's usually extremely slow. I'm not sure why but I believe it doesn't return until the console graphically shows the outputted string. Additionally you can't mmap() to stdout.

Writing to a file should be much faster (but still orders of magnitude slower than computing a hash, all I/O is slow).