Assistance needed with this if/else: linear equation assignment for school

Question

Problem: Write a program that solves the linear equation for x, where ax = b in integers.

Given two user inputs, a and b (a may be zero), print:

a single integer solution for x if it exists or
"no solution" or
"no integer solution" if the answer is a floating point number or
"many solutions"

How can I solve this using if elif and else statements? Here's my code so far:

a = int(input())
b = int(input())

if a == 0 and b == 0:
  print("many solutions")
elif b //a == 0:
  print(b // a)
elif b//a != 0:
  print("no integer solution")
elif a== 0 and b!= 0 or b==0 and a!=0:
  print("no solution")

I have transcribed your code from the image. It is more useful if you could paste it though. For example because it looks like you have some weird indentation on line 9 in your screenshot (which I did not transcribe) — lucidbrot, Jan 28 '21 at 14:17
Also, is there something specific you're having problems with? — lucidbrot, Jan 28 '21 at 14:18
so i dont know in what condition would x have 1 solution in this linear equation , if i know that i could do this. — ali jibran, Jan 28 '21 at 14:21
and i can't paste the image because im a new user and require 10 reputation — ali jibran, Jan 28 '21 at 14:21
I meant you should paste the code as text instead of as an image. That makes it possible for us to run and modify it easily, and maintains things like indentation issues. — lucidbrot, Jan 28 '21 at 14:23
If share some simple input and output it could be very helpful for other people to help you.. — Daniel Hao, Jan 28 '21 at 14:24

score 2 · Accepted Answer · answered Jan 28 '21 at 14:26

2

In your 'elif' statements, you have given:

elif b //a == 0:
    print(b // a)
elif b//a != 0:
    print("no integer solution")

The operator '//' is used for integer division i.e. leaving no remainder. Hence the elif statement will always execute.

I assume you're checking the remainder. For that use '%'. This returns the remainder

answered Jan 28 '21 at 14:26

Ismail Hafeez

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If this helped kindly upvote this answer and mark it as correct. Appreciate it! – Ismail Hafeez Jan 28 '21 at 14:27
thank you for help!! i gave you the upvote but my reputation is too low for it to show :( – ali jibran Jan 28 '21 at 14:55
That's ok. Can you select this as the correct answer? Click on the check button under the votes. – Ismail Hafeez Jan 28 '21 at 14:57

score 0 · Answer 2 · answered Jan 28 '21 at 14:30

print:

a single integer solution for x if it exists or "no solution"

or "no integer solution" if the answer is a floating point number

or "many solutions".

Let's first think about the math: You have the equation a*x = b and you want to find x. The first step is to solve this equation on paper so that you get it to the form x = ....

Now you will have a division in there. And divisions are always risky because if you divide by zero, you will get a ZeroDivisionError. So In the program, I would first of all handle that case. Think about what it should do when that variable is indeed zero.

so i dont know in what condition would x have 1 solution in this linear equation

In most cases. The only reason to have more or less than 1 solution is if either a division by zero happens or there is no integer solution at all.

To check if there is an integer solution, you can use the modulo operator. Or you could compute the integer result and then compute it backwards again to see if you get the result that was your input.

To code this, I think you have understood how if and elif work. Just make sure you have the same number of whitespace in front of the indented lines that should be at the same level. Otherwise it will probably not run.

Assistance needed with this if/else: linear equation assignment for school

2 Answers2