Compose a tune that integrates the letter-based representation of the determined musical pattern and the given melodic idea.
X:1
L:1/8
M:4/4
K:A
['a2 ga (3faf ec dcdf e2', 'AB c2 e2 A2', 'A,2 A,B,']  
X:1
L:1/8
M:4/4
K:A
 a2 ga (3faf ec | dcdf e2 ef | a2 ba gfed | BAGB A2 b2 | a2 ga (3faf ec | dcdf e2 e2 | cBAc ecAc | 
 BAGB A2 AB |: c2 e2 A2 AB | c2 e2 A2 AB | c2 e2 A2 e2 |1 EFGB A2 AB :|2 EFGB A2 A2 |: 
[K:Amix] A2{B} A2 GFED | F2 F2 E2 E2 |1 A2{B} A2 GFED | FEDF EDCE :|2 FGAG FEDF | EDCE A,2 A,B, |: 
[K:A] C2 EC A,2 A,B, | C2 EC A,2 A,B, |1 C2 E2 A,2 E2 | B,2 EB, A,2 A,B, :|2 C2 EC A,2 E2 | 
 B,4 A,4 ||  