Go: package main

import (
	"bufio"
	"fmt"
	"math/big"
	"os"
	"strconv"
)

var sc = bufio.NewScanner(os.Stdin)

func main() {
	sc.Scan()
	dataset, _ := strconv.Atoi(sc.Text())
	var firstdata *big.Int

	for i := 0; i < dataset*2; i++ {
		n := new(big.Int)
		sc.Scan()
		data, _ := n.SetString(sc.Text(), 10)

		if i%2 == 0 {
			firstdata = data
			continue
		}

		result := new(big.Int)
		if result := result.Add(data, firstdata); len(result.String()) > 80 {
			fmt.Println("overflow")
			continue
		} else {
			fmt.Println(result)
		}
	}
}

Python: while(True):
    try:
        n = input()
        for i in range(n):
            a = input()
            b = input()
            c = str(a + b)
            if(len(c) > 80):
                print("overflow")
            else:
                print(c)
    except Exception:
        break

Python: def main():
    n = int(input())

    for i in range(n):
        result = str(int(input()) + int(input()))

        if len(result) > 80:
            print("overflow")
        else:
            print(result)

if __name__ == '__main__':
    main()

Python: from sys import stdin
n = int(stdin.readline())
for i in range(n):
    c = str(int(stdin.readline().strip()) + int(stdin.readline().strip()))
    if (len(c) > 80):
        print("overflow")
    else:
        print(c)

Python: n=int(input())
for i in range(n):
	a=int(input())
	b=int(input())
	if len(str(a+b))>80:print("overflow")
	else:print(a+b)

Python: import math
for i in range(int(input())):
    a = int(input())
    b = int(input())
    if int(math.log10(a+b) + 1) > 80:
        print("overflow")
    else:
        print(a+b)

Python: n=int(input())
for _ in range(n):
	s=int(input())+int(input())
	print('overflow' if s/1e80>1 else s)

Python: n=int(input())
ans_list=[]

for i in range(n):
	a=int(input())
	b=int(input())
	ans_list.append(a+b)

for i in ans_list:
	print(i)

Python: while 1:
    try:
        n = int(input())
    except:break

    n1 = 0
    n2 = 0
    for i in range(n):
        n1 = int(input())
        n2 = int(input())
        isOver = False
        ans = n1 + n2
        if len(str(ans)) >= 81 | len(str(n1)) | len(str(n1)) :
            isOver = True
        if isOver:
            print("overflow")
        else:
            print(ans)

Python: n = int(input())
 
for i in range(n):
    a = int(input())
    b = int(input())
 
    if (a + b) < (10 ** 80):
        print(a + b)
    else:
        print("overflow")

Python: n = int(input())

for i in range(n):
    x = input()
    y = input()
    ans = int(x) + int(y)
    if len(x) > 80 or len(y) > 80 or len(str(ans)) > 80:
        print("overflow")
    else:
        print(ans)

Python: from math import log10
n = int(input())
for i in range(n):
    a = int(input())
    b = int(input())
    c = a+b
    if (log10(c) > 80):
        print("overflow")
    else:
        print(c)

Python: import math

c  = input();

for var in range(0, int(c)) :
	n1 = input();
	n2 = input();
	sum = int(n1) + int(n2);

	if int(math.log10(sum)) + 1 > 80 :
		print("overflow");
	else :
		print(sum);

Python: times=int(input())
for i in range(times):
    a=int(input())
    b=int(input())
    if len(str(a))<=80 and len(str(b))<=80 and len(str(a+b))<=80:
        print(a+b)
    else: print("overflow")

Python: n = int(raw_input())
for _ in [0]*n:
  a = int(raw_input())
  b = int(raw_input())
  c = a+b
  print [c,"overflow"][len(str(c))>80]

Python: for i in range(int(input())):
    a = sum([int(j) for j in input().split()])
    if a > 2147483647:
        print("overflow")
    else:
        print(a)

Python: import sys

n = int(input())
for _ in range(n):
    a = sys.stdin.readline()
    b = sys.stdin.readline()
    c = int(a) + int(b)
    if len(str(c)) > 80:
        print("overflow")
    else:
        print(c)

Python: n=input()
for i in xrange(n):
    a=0
    for j in xrange(2):
        a+=input()
    if len(str(a))>80:
        print('overflow')
    else:
        print(a)

Python: [print((lambda x:x if x<10**80 else "overflow")(int(input())+int(input()))) for i in range(int(input()))]

Python: N = int(input())
for _ in range(N):
    f, s = [int(input()) for _ in range(2)]
    print(f+s if len(str(f+s)) <= 80 else "overflow")

Python: 
n=int(input())
for _ in range(n):
    a=input()
    b=input()
    s=int(a)+int(b)
    if len(a)>80 or len(b)>80 or len(str(s))>80:
        print("overflow")
        continue
    else:
        print(s)

Python: N=int(input())
for i in range(N):
    a=int(input())
    b=int(input())
    retval=a+b
    if len(str(retval))>80:
        print("overflow")
    else:
        print(retval)

Python: #!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Copyright  : @Huki_Hara
# Created    : 2015-03-05

n=int(input())

for _ in range(n):
    a=int(input())
    b=int(input())
    sum=a+b
    if len(str(sum)) > 80:
        print("overflow")
    else:
        print(sum)

Python: [print(i) if len(i)<=80 else print("overflow") for i in map(str,[sum([int(input()) for j in range(2)]) for i in range(int(input()))])]

Python: n = int(input())
for i in range(n):
    s = int(input()) + int(input())
    if len(str(s)) <= 80:
        print(s)
    else:
        print('overflow')

Python: N = int(input())
import re
for _ in [0]*N:
    a = input().zfill(100)
    b = input().zfill(100)
    result = []
    prev = 0
    for i in range(1, 81):
        n = int(a[-i]) + int(b[-i]) + prev
        result.append(n%10)
        prev = n // 10
    if prev > 0 or int(a[:21]) + int(b[:21]) > 0:
        print("overflow")
    else:
        result = "".join(map(str, result[::-1]))
        print(int(result))

Python: import sys

n = int(input())
for i in range(n):
    a = int(input())
    b = int(input())
    if a + b >= 10**80:
        print ("overflow")
    else:
        print(a + b)

Python: import math

n = int(input())
for i in range(n):
    for i in range(2):
        x = int(input())
        y = int(input())
        result = x + y
        print(result) if math.log10(result) + 1 < 10 ** 80 else print("overflow")

Python: n=int(input())

for i in range(n):
    a=int(input())
    b=int(input())
    c=a+b
    if len(str(c))>80:
        print("overflow")
    else:
        print(c)

Python: n = int(input())
for _ in range(n):
    a, b = int(input()), int(input())
    x = str(a+b)
    print('overflow' if len(x) > 80 else a+b)

Python: for _ in range(int(input())):
    a = int(input()) + int(input())
    print(a if len(str(a)) < 81 else "overflow")

Python: #!/bin/python

def largeBudget(a, b):
  if a+b > 10e+80:
    print("overflow")
  else:
    print("%d"%(a+b))

N = int(input())
for i in range(N):
  a = int(input())
  b = int(input())
  largeBudget(a, b)

Python: n = int(input())
for i in range(0, n) :
  a, b = list(map(int, input().split()))
  sum = a + b
  if str(sum).length() > 80 :
    print("overflow")
  else :
    print(sum)

Python: n=int(input())
for i in range(n):
    a=int(input())
    b=int(input())
    if a+b>=10**79:print("overflow")
    else:print(a+b)

Python: if __name__ == "__main__":
    nset = int(input())

    for i in range(0, nset):
        sa = input()
        sb = input()
        a = int(sa)
        b = int(sb)
        c = a + b

        if len(sa) > 80 or len(sb) > 80 or len(str(c)) > 80:
            print("overflow")
        else:
            print(c)

Python: n = int(input())
for i in range(n):
    a = int(input())
    b = int(input())
    if len(str(a + b)) > 80:
        print("overflow")
    else:
        print(str(a + b))

Python: n=int(input())
for i in range(n):
	a=int(input())
	b=int(input())
	c=a+b
	c=str(c)
	if len(c)>80:
		print("overflow")
	else:
		print(c)

Python: # AOJ 0015 National Budget
# Python3 2018.6.9 bal4u

n = int(input())
for i in range(n):
    s = int(input()) + int(input())
    if len(str(s)) <= 80:
        print(s)
    else:
        print('overflow')

Python: N = int(input())
for _ in range(N):
	a = int(input())
	b = int(input())
	if len(str(a+b)) > 80:
		print("overflow")
	else:
		print(a+b)