#! -*- coding: utf-8-unix -*-

import sys



# if __name__=='__main__':

#   lines = [int(x.strip()) for x in sys.stdin.readlines()]

#   print lines

#   n = lines[0]

# for i in xrange(n):

#     # a, b  = int(lines[i+1]), int(lines[i+2])

#     a, b  = lines[2*i+1], lines[2*i+2]

#     if len(str(a+b)) > 80:

#       print 'overflow'

#     else:

#       print a+b



if __name__=='__main__':

  # lines = [int(x.strip()) for x in sys.stdin.readlines()]

  # n = lines[0]

  n = eval(input())

for i in range(n):

    # a, b  = int(lines[i+1]), int(lines[i+2])

    # a, b  = lines[2*i+1], lines[2*i+2]

    a, b  = eval(input()), eval(input())

    if len(str(a+b)) > 80:

      print('overflow')

    else:

      print(a+b)
import sys



if __name__=='__main__':

  lines = [int(x.strip()) for x in sys.stdin.readlines() if x != '' and x != '\n']

  n = lines[0]

for i in range(n):

  a, b  = lines[2*i+1], lines[2*i+2]

  if len(str(a+b)) > 80:

    print('overflow')

  else:

    print(a+b)
#! -*- coding: utf-8-unix -*-
import sys

# if __name__=='__main__':
#   lines = [int(x.strip()) for x in sys.stdin.readlines()]
#   print lines
#   n = lines[0]
# for i in xrange(n):
#     # a, b  = int(lines[i+1]), int(lines[i+2])
#     a, b  = lines[2*i+1], lines[2*i+2]
#     if len(str(a+b)) > 80:
#       print 'overflow'
#     else:
#       print a+b
if __name__ == "__main__":
    # lines = [int(x.strip()) for x in sys.stdin.readlines()]
    # n = lines[0]
    n = eval(input())
for i in range(n):
    # a, b  = int(lines[i+1]), int(lines[i+2])
    # a, b  = lines[2*i+1], lines[2*i+2]
    a, b = eval(input()), eval(input())
    if len(str(a + b)) > 80:
        print("overflow")
    else:
        print(a + b)

import sys

if __name__ == "__main__":
    lines = [int(x.strip()) for x in sys.stdin.readlines() if x != "" and x != "\n"]
    n = lines[0]
for i in range(n):
    a, b = lines[2 * i + 1], lines[2 * i + 2]
    if len(str(a + b)) > 80:
        print("overflow")
    else:
        print(a + b)

-#! -*- coding: utf-8-unix -*- -# if __name__=='__main__': -#   lines = [int(x.strip()) for x in sys.stdin.readlines()] -#   print lines -#   n = lines[0] -# for i in xrange(n): -#     # a, b  = int(lines[i+1]), int(lines[i+2]) -#     a, b  = lines[2*i+1], lines[2*i+2] -#     if len(str(a+b)) > 80: -#       print 'overflow' -#     else: -#       print a+b -    # lines = [int(x.strip()) for x in sys.stdin.readlines()] -    # n = lines[0] -    n = eval(input()) +    lines = [int(x.strip()) for x in sys.stdin.readlines() if x != "" and x != "\n"] +    n = lines[0] -    # a, b  = int(lines[i+1]), int(lines[i+2]) -    # a, b  = lines[2*i+1], lines[2*i+2] -    a, b = eval(input()), eval(input()) +    a, b = lines[2 * i + 1], lines[2 * i + 2]