text=\'A(3)B(1)D(5)C(2)\'
tokens=[]
i=0
while i<len(text):
    c=text[i]
    if c==\'(\':
        i+=1
        c=text[i]
        value=\'\'
        while c!=\')\':
            value+=c
            i+=1
            c=text[i]
        tokens.append(int(value))
        i+=1
        continue
    tokens.append(c)
    i+=1
output=\'\'
for i in range(len(tokens)//2):
    output+=tokens[i*2]*tokens[i*2+1]
print(output)

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