An M digit non negative integer n is a Langford Pairing of length M if it has the following properties It has an even number of digits (so M is even, although the number n does not have to be even) It contains 2 copies of each of the digits from 1 to M 2 Its two 1s have one digit between them, its ...

Python program def isLangfordPairingn Convert n to a string to iterate through its digits ...

An M-digit non-negative integer n is a Langford Pairing of length M if it has the following

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An M-digit non-negative integer n is a Langford Pairing of length M if it has the following properties:

It has an even number of digits (so M is even, although the number n does not have to be even).
It contains 2 copies of each of the digits from 1 to M/2.
Its two 1s have one digit between them, its two 2's have two digits between them, etc. In general, the two instances of a digit k have k digits between them.

For example, n=41312432 is a Langford pairing of length M=8, because the two 1's have one digit between them (a three). The two 2's have two digits between them (a four and a three), etc.

With this in mind, write the function isLangfordPairing(n) which takes an integer n, and returns True if it is a Langford Pairing, and False otherwise.