ARITH - Simple Arithmetics

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One part of the new WAP portal is also a calculator computing expressions with very long numbers. To make the output look better, the result is formated the same way as is it usually used with manual calculations.

Your task is to write the core part of this calculator. Given two numbers and the requested operation, you are to compute the result and print it in the form specified below. With addition and subtraction, the numbers are written below each other. Multiplication is a little bit more complex: first of all, we make a partial result for every digit of one of the numbers, and then sum the results together.


There is a single positive integer T on the first line of input (equal to about 1000). It stands for the number of expressions to follow. Each expression consists of a single line containing a positive integer number, an operator (one of +, - and *) and the second positive integer number. Every number has at most 500 digits. There are no spaces on the line. If the operation is subtraction, the second number is always lower than the first one. No number will begin with zero.


For each expression, print two lines with two given numbers, the second number below the first one, last digits (representing unities) must be aligned in the same column. Put the operator right in front of the first digit of the second number. After the second number, there must be a horizontal line made of dashes (-).

For each addition or subtraction, put the result right below the horizontal line, with last digit aligned to the last digit of both operands.

For each multiplication, multiply the first number by each digit of the second number. Put the partial results one below the other, starting with the product of the last digit of the second number. Each partial result should be aligned with the corresponding digit. That means the last digit of the partial product must be in the same column as the digit of the second number. No product may begin with any additional zeros. If a particular digit is zero, the product has exactly one digit -- zero. If the second number has more than one digit, print another horizontal line under the partial results, and then print the sum of them.

There must be minimal number of spaces on the beginning of lines, with respect to other constraints. The horizontal line is always as long as necessary to reach the left and right end of both numbers (and operators) directly below and above it. That means it begins in the same column where the leftmost digit or operator of that two lines (one below and one above) is. It ends in the column where is the rightmost digit of that two numbers. The line can be neither longer nor shorter than specified.

Print one blank line after each test case, including the last one.


Sample Input:


Sample Output:




Warning: large Input/Output data, be careful with certain languages.

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n0xne: 2022-03-17 11:21:59

Completed it in 114 lines and about 1 hours in CPP, working fine in my console even in ideone. But for some reason I am getting SIGABRT runtime error. They should provide some more debug info, I don't wanna debug this code now.

guru_shreyansh: 2021-08-03 20:13:36

Solved this after 2 WAs with 130 lines of Java code. For Java coders, use StringBuilder, BigInteger, String.format() for easier implementation.

Rafa³ Ochtera: 2021-05-15 02:34:00

I don't get the confusion about dashes. Maybe it was added later but the second to last akapit is almost entirely about how dashes should work. As some stated the problem is trivial but the implementation is challenging. Which I took as oportunity to practice TDD and I glad I did. Dodged few bullets with tests early on.

ysnikhil: 2021-04-25 18:03:34

the part including "+" and "-" are not required. If one can solve it for "*", then he surely can do it for "+" and "-". So, one should only attempt for "*" and save some time.

derekhail: 2020-10-14 18:27:45

This is sheer amount of time waste

jjprioli: 2020-08-10 05:13:33

I am coming to the same conclusion as @presnelberg. This is absurd. I have code that is functioning perfectly well. Project Euler gives you the data file. OK. HackerRank hides the data files, but gives you a chance to earn peeks at troublesome cases. SPOJ chooses not to do either; that is their prerogative, but I am beginning to get weary of "clever" problem designers relying on unclear or unspecified specifications to trap me.

louiszhou: 2020-07-25 22:31:59

But the single problem is, that i have the completely right answer, but judging give me a error: runtime Exception, it's such like the exception in Java, but i have done it in C.

Don't know why...

louiszhou: 2020-07-25 22:28:39

Well, this problem is really great.
I did it in 4 hours with like 180 rows
The logic is actually not so easy but also not so difficult, if you think more!
I'm 14 years old, and i learned programming just 2 months.
It was really amazing, that i did it all by myself and did not took so many time!

Last edit: 2020-07-25 22:39:56
sia_sony1234: 2020-06-24 15:36:42

I completely correct answer but judging giving me wrong answer all time

wlata: 2020-06-10 11:40:21

Is there any way to tell if the result has N+M or rather N+M-1 digits without calculating the result itself?

Added by:adrian
Time limit:5s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL6 VB.NET
Resource:ACM Central European Programming Contest, Prague 2000