# Amazon Online Assessment 2021 (OA) - Find Valid Discount Coupons

At Amazon's annual sale. employees are tasked with generating valid discount coupons for loyal customers. However, there are some used/invalid coupons in the mix and the challenge in this task is to determine whether a given discount coupon is valid or not.

The validity of a discount coupon is determined as follows:

1. An empty discount coupon is valid.
2. If a discount coupon A is valid, then a discount coupon C made by adding one character x to both the beginning of A and the end of A is also valid (i.e the discount coupon C = xAx is valid).
3. If two discount coupons A and B are vand, then the concatenation of B and A is also valid (i.e the coupons AB and BA are both valid).

Given n discount coupons, each coupon consisting of only lowercase English characters, where the ith discount coupon is denoted discounts[i], determine if each discount coupon is valid or not. A valid coupon is denoted by 1 in the answer may while an invalid coupon is denoted by 0.

### Input

• `discounts`: Array of discount coupons.

### Output

Array of integers, a valid coupon is denoted by 1 and an invalid coupon is denoted by 0.

### Examples

#### Example 1:

Input:

``1discounts = ['abba', 'abca']``

Output: `[1, 0]`

Explanation:

'abba' is valid and 'abca' is invalid.

## Title

### Script

Lorem Ipsum is simply dummy text of the printing and typesetting industry. `Lorem` `Ipsum` has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.

Contrary to popular belief, `Lorem` `Ipsum` is not simply random text.

``````1  >>> a = [1, 2, 3]
2  >>> a[-1]
3  3``````

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