Is it more secure to use two hash function like mod1=1e9+7 mod2= 1e9+9 for calculating hash value ???
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Is it more secure to use two hash function like mod1=1e9+7 mod2= 1e9+9 for calculating hash value ???
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Yes it is. But even 8 hashes still can be hacked . So the best thing to do is to use random:
One popular approach is to store several modulo values and several bases and choosing them randomly.
I prefer to not mess with modulus but to choose random base instead(like random number in range [l;r]) (remember that it should always be greater than size of alphabet).
Also remember to use good random number generator.