You are an expert in program synthesis. You are tasked with solving a Syntax-Guided Synthesis (SyGuS) problem. Your goal is to output a function that should produce outputs that satisfy a series of constraints when given specific inputs.

Question:
(set-logic SLIA)

(synth-fun f ((firstname String) (lastname String)) String)

(declare-var firstname String)
(declare-var lastname String)
(constraint (= (f "Launa" "Withers") "Launa Withers"))
(constraint (= (f "Lakenya" "Edison") "Lakenya Edison"))
(constraint (= (f "Brendan" "Hage") "Brendan Hage"))
(constraint (= (f "Bradford" "Lango") "Bradford Lango"))
(constraint (= (f "Rudolf" "Akiyama") "Rudolf Akiyama"))
(constraint (= (f "Lara" "Constable") "Lara Constable"))

(check-synth)
Solution:
(define-fun f ((firstname String) (lastname String)) String (str.++ firstname (str.++ " " lastname)))

Question:
(set-logic SLIA)

(synth-fun f ((firstname String) (lastname String)) String)

(declare-var firstname String)
(declare-var lastname String)
(constraint (= (f "Launa" "Withers") "L. Withers"))
(constraint (= (f "Lakenya" "Edison") "L. Edison"))
(constraint (= (f "Brendan" "Hage") "B. Hage"))
(constraint (= (f "Bradford" "Lango") "B. Lango"))
(constraint (= (f "Rudolf" "Akiyama") "R. Akiyama"))
(constraint (= (f "Lara" "Constable") "L. Constable"))

(check-synth)
Solution:
(define-fun f ((firstname String) (lastname String)) String (str.++ (str.++ (str.++ (str.at firstname 0) ".") " ") lastname))

Question:
(set-logic SLIA)

(synth-fun f ((firstname String) (lastname String)) String)

(declare-var firstname String)
(declare-var lastname String)
(constraint (= (f "Nancy" "FreeHafer") "Nancy F."))
(constraint (= (f "Andrew" "Cencici") "Andrew C."))
(constraint (= (f "Jan" "Kotas") "Jan K."))
(constraint (= (f "Mariya" "Sergienko") "Mariya S."))

(check-synth)
Solution:
(define-fun f ((firstname String) (lastname String)) String (str.++ (str.++ (str.++ firstname " ") (str.at lastname 0)) "."))

Question:
(set-logic SLIA)

(synth-fun f ((firstname String) (lastname String)) String)

(declare-var firstname String)
(declare-var lastname String)
(constraint (= (f "Launa" "Withers") "L. Withers"))
(constraint (= (f "Lakenya" "Edison") "L. Edison"))
(constraint (= (f "Brendan" "Hage") "B. Hage"))
(constraint (= (f "Bradford" "Lango") "B. Lango"))
(constraint (= (f "Rudolf" "Akiyama") "R. Akiyama"))
(constraint (= (f "Lara" "Constable") "L. Constable"))

(check-synth)
Solution:
