def findlengthofterm(n):
    if n == 1:
        return len(A)
    elif n==2:
        return len(B)

    a=len(A)
    b=len(B)
    c=0
    i=2
    while(i<n):
        c= a+b
        a,b=b,c
        i+=1
    return c

def findIndex(n) : 
      
    if (n <= 1) : 
        return n 
   
    a = len(A)
    b = len(B)
    c = 0
    res = 2

    while (c < n) : 
        c = a + b            
        res = res + 1
        a = b 
        b = c 
          
    return res

if __name__=='__main__':    
    num = int(input())
    output =[]
    for i in range(num):
        A,B, x = input().split()
        s=int(x)
        n=findIndex(s)
        a=s
        while(n > 2):
            l=findlengthofterm(n-2)
            if a>l:
                a=a-l
            else:
                n-=1
            n-=1

        if n==1:
            output.append(A[a-1])
        else:
            output.append(B[a-1])
						
    for out in output:
        print(out)