[swim_5318]

I need to write a pseudo code of an algorithm that returns 1 if every element of array A is in Array B, and 0 otherwise.
I know I need to sort both arrays first then I want to do a linear compare.... I just don't know how to write it. Here is what I have. Some guidance would be great, Thanks!

Algorithm arrayEqual(A, B )
Input: Arrays A and B of n elements
Ouput: 1 or 0

This post has been edited by swim_5318: 13 September 2012 - 03:13 AM

[Cuzzie]

I don't think you need to sort the arrays. You can use 2 for loops to compare the elements in both array A and array B. Also, you will need an integer that defaults to 1. Change it to 0 if you find any element in array A that doesn't exist in array B.

[CasiOo]

Cuzzie, on 13 September 2012 - 10:41 AM, said:

I don't think you need to sort the arrays. You can use 2 for loops to compare the elements in both array A and array B. Also, you will need an integer that defaults to 1. Change it to 0 if you find any element in array A that doesn't exist in array B.

True he doesn't need to sort the arrays. You don't have to declare an integer to hold the value 1/0 and change it on the way. When you find an element that is not in array B you return 0 immediatly, no need to save it. If the checking has finished without the method returning, you would then return 1.

edit: You said you wanted a linear compare, but what if the sorted arrays are like these

int[] a1 = { 5, 6, 20, 22 };
int[] a2 = { 5, 6, 8, 10, 11, 13, 16, 17 20, 22 };

This post has been edited by CasiOo: 13 September 2012 - 04:18 AM

[swim_5318]

Okay, now I am lost. What would my loop look like to get them to compare? So I need Array A elements to compare one at a time to the B array?

[DavsX]

for every item in array A:
- Is it in array B? yes -> do nothing; no -> return 0 ;
return 1;

[jon.kiparsky]

CasiOo, on 13 September 2012 - 06:12 AM, said:

True he doesn't need to sort the arrays.

However, it'll save a lot of time if he does, as the size of the arrays gets large.

[pbl]

lot less iterations... just compare one by one and return 0 if not found