notes

QuadraticProbing.md (605B)

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 # Quadratic Probing
 
 Ch 5
 
 **Definition:** Quadratic probing is a probing strategy where we start with the input and then alternately move right and left by successive perfect squares. 
 
 Basically, we check first e then e + 1 then then e - 1 then e + 4 then e - 4 and so on.
 
 Note:
 
 This only works with specific array sizes because some sizes don't get entirely mapped to by the probing function for all valid values of e.
 
 Implementation in code:
 
 ```c#
 
 for(int i = 0 ; i < 10 ; ++i){
 	int n = (i + 1) / 2;
 	if(i % 2 == 0){
 		Console.WriteLine(n * -n);
 	}
 	else{
 		Console.WriteLine(n * n);
 	}
 }
 
 ```