Question

20. [5 points] Rewrite the following ML. function using patterns fun factn. ifn-0 then 1 else n fact (n-1) 21. [S points) Using map function, write an ML function int2real of type int list real list that takes a list of integers and returns the same numbers converted to real. For example, if the input is [1,2,3], the output should be like [1.0,2.0,3.0 22. [5 points] Using foldr function, write a function duplist of type·a list 'a list that takes a list of integers and returns the same input list, but with each element is repeated twice. For example, if the input is [1,2,3], the output should be [1,1,2,2,3,3]. 23. [10 points] Write an ML function isPrime of type int ->bool that returns true if and only if its integer parameter is a prime number. 24. [10 points] Write a simple java function onReceive that receives a message from an actor which contains an integer number, calculate the square value of this integer, then send the result back to th sender actor using tell method. public void onReceive (Object message) (

Answer 1

SOLUTION:-

SOLUTION-(20):- Term rewriting is a restricted form of pattern matching that has numerous applications within the programming language domain. Rather than using the if construct to separate the subdomains, we will utilize term rewriting in order to indicate each separate case in the function definition by pattern matching fun facto 1 fact nn * fact (n-1) Here, each subdomain is separated by ML will replace the function call by the appropriate definition.
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