Help writing a program in C++ that searches a text file (that has no spaces in it) named input.txt for the substring that is the longest without repeating characters. A program must be written in main to read and process input.txt, and the then the output will be in output.txt. Use a function to determine the substring and length of the substring instead of writing the entire program in the main function. The output in output.txt must be formatted neatly (use setw).

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Ex:

input.txt contains:

qwhgjuiopqihjk

abc

b

mmmmmm

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output.txt will contain the text from input.txt followed by the substring and number of characters in the substring:

qwhgjuiopqihjk qwhgjuiop 9

abc abc 3

b b 1

mmmmmm m 1

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If possible please explain the process of the code for help in better understanding! Thank you!