Using ML programming language which takes as input, two strings, and returns true if and only if the second string

is part of the first string. $($Hint: Use the function explode learned in the class to

break strings into lists of characters$)$

Examples:

parts$("$johnjay$",$ "ohnj"$)=$ true

parts$("$johnjay$",$ "jay"$)=$ true

parts$("$johnjay$",$ "johns"$)=$ false