How to create a hash from 3 ordered int?

Question

Let's say I have a structure like this,

struct point3d{

  int x;

  int y;

  int z;

};

How can I create a hash value from this structure? Thanks

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Reopened. The so-called dupe was for `std::size_t`, not for `int`. The latter has restrictions on overflow and bitwise shifting. — Bathsheba, Jan 22 '19 at 11:33

score -1 · Answer 1 · answered Jan 22 '19 at 11:49

A lot depends on what you want to achieve and how much distribution you need.

Most non-cryptographic hash would be similar to :

int64_t Hash(const point3d & point){
       int64_t start = 1234; //magic number
       int64_t multiplier = 3467; //some other magic number
       int64_t hash = start + point.x;
       hash = hash*multiplier + point.y;
       hash = hash * multiplier + point.z;
       return hash;

}

Test this out on your data set by tuning start and multiplier.

How to create a hash from 3 ordered int?

1 Answers1