Update for 03-05-22 20:45

tech/algorithms.wiki

@@ -90,5 +90,6 @@ Different ways to store and operate on data, with differing efficiency
 == Misc ==
 
 * [[p_vs_np]]
+* [[quadratic_probing]]
 
 [[index]]

tech/hash_table.wiki

@@ -11,6 +11,7 @@ flavors.
 == Bad for ==
 
 * Non basic data types (unless you create a really good hash function)
+  * also see [[quadratic_probing]]
 
 == Optimize ==
 

tech/quadratic_probing.wiki

@@ -0,0 +1,16 @@
+= Quadratic Probing =
+
+Quadratic probing is a scheme for resolving hash collisions in [[hash_table]]s.
+It operates by taking the original hash index and adding sucessive values of an
+arbitrary quadratic polymoial until an open solt is found.
+
+== Example ==
+
+For some `h(k)` that is a hash function, mapping to the keyspace [0, m-1],
+where m is the size of a hash table, let the _i_th probe position for some _k_
+be,
+{{{
+h(k,i) = h(k) + c1i + c2i^2 mod m
+  }}}
+
+Where c2 != 0 and c1 and c2 are constants.