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contains

Language/Type: JavaScript arrays
Author: Melissa Medsker-Galloway (on 2016/11/18)

Write a function named contains that accepts two arrays a1 and a2 as parameters and that returns a boolean value indicating whether or not a2's sequence of elements appears in a1 (true for yes, false for no). The sequence of elements in a2 may appear anywhere in a1 but must appear consecutively and in the same order. For example, if variables called a1 and a2 store the following values: 

var a1 = [1, 6, 2, 1, 4, 1, 2, 1, 8];
var a2 = [1, 2, 1];

Then the call of contains(a1, a2) should return true because a2's sequence of values [1, 2, 1] is contained in a1 starting at index 5. If a2 had stored the values [2, 1, 2], the call of contains(a1, a2) would return false because a1 does not contain that sequence of values. Arrays may also include non-integer values, such as doubles or strings. Anything that would be considered equal using JavaScript's "==" comparison should be considered equivalent in this function. For example, if variables called a3 and a4> store the following values: 

var a3 = [false, true, "1", 2.0, 3];
var a4 = ["true", 1, "2"];

Any two arrays with identical elements are considered to contain each other, so a call such as contains(a1, a1) should return true.

You may assume that both arrays passed to your method will have lengths of at least 1.

Type your solution here:


This is a function problem. Write a JavaScript function as described. Do not write a complete program; just the function(s) above.

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