Shell Script for getting lines after and before of search String

Sometime when we search some text string in Unix environment we need those strings also which come before or after that searched string.
This below small shell-script gives same output and return output in one file depends on user choice that how many no. of lines user wants to print after and before any searched string.

This script take input as search string and no. of line you want to print before and after search result line and give output in search.txt

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