WA, test 2

N=int(input())

s=0

for i in range(N):

x,y=map(int,input().split())

s*=10

s+=(x+y)

print(s)

Re: WA, test 2

s is one digit by definition

But if a+b>=10 s can be expressed only using two digits

Re: WA, test 2

Ohh, wait...

Try print(int(s))

I suppose you print in scientific notation when s is huge