import sys
ctr=0
up=raw_input()
tocal=raw_input()
while ctr!=int(up):
    l=tocal.split(' ')
    num1=(l[0])[::-1]
    num2=(l[1])[::-1]
    while int(num1)%10 ==0 or int(num2)%10==0:
        if num1%10==0:
            num1=num1[:-1]
        elif num2%10==0:
            num2=num2[:-1]
 
 
    sum=int(num1)+int(num2)
    while sum%10==0:
        sum=int(str(sum)[:-1])
 
    rsum=str(sum)[::-1]
 
    print rsum
    ctr+=1
    tocal=raw_input()
 
sys.exit(0)    

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