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Counting unique elements in a very large array

if there are 1000000000 numbers,how can i find the distinct number. c wont support 10^9 arrays na?
Jan 7 '12 #1
2 1653
donbock
2,426 Expert 2GB
If you can't hold the entire array in memory then you will need to store portions of the array in temporary files. Take a look at merge sort.
Jan 10 '12 #2
weaknessforcats
9,208 Expert Mod 8TB
You might SQL (written in C) where you set up your array as a table and then do a simple SELECT.
Jan 11 '12 #3

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