NZEC error in Python

While coding in various competitive sites, many people must have encountered NZEC errors. NZEC (non zero exit code) as the name suggests occurs when your code is failed to return 0. When a code returns 0 it means it is successfully executed otherwise it will return some other number depending on the type of error. When the program ends and it is supposed to return “0” to indicate if finished fine and is not able to do so it causes NZEC. Of course, there are more cases associated with NZEC.

Why does NZEC occur?(one example)

In python, generally, multiple inputs are separated by commas and we read them using input() or int(input()), but most of the online coding platforms while testing give input separated by space and in those cases, int(input()) is not able to read the input properly and shows error like NZEC.

How to resolve?

For Example, Think of a simple program where you have to read 2 integers and print them(in the input file both integers are in same line). Suppose you have two integers as shown below: 23 45 Instead of using :

n = int(input())
k = int(input())

Use:

n, k = raw_input().split(" ")
n = int(n)
k = int(k)

to delimit input by white spaces.

Wrong code

Python

n = int(input())
k = int(input())
print(n," ",k)

Input: 2 3

 When you run the above code in IDE with the above input you will get error:-

Traceback (most recent call last):
  File "b712edd81d4a972de2a9189fac8a83ed.py", line 1, in 
    n = int(input())
  File "", line 1
    2 3
      ^
SyntaxError: unexpected EOF while parsing

The above code will work fine when the input is in 2 two different lines. You can test yourself. To overcome this problem you need to use split.

Correct code

Python

n,k=input().split()
n = int(n)
k = int(k)
print(n," ",k)

Input:

7 3

Output:

7   3

Some prominent reasons for NZEC error

1. Infinite Recursion or if you have run out of stack memory.
2. Input and output are NOT exactly same as the test cases.
3. As the online platforms, test your program using a computer code which matches your output with the specified outputs exactly.
4. This type of error is also shown when your program is performing basic programming mistakes like dividing by 0.
5. Check for the values of your variables, they can be vulnerable to integer flow.

There could be some other reasons also for the occurrence NZEC error, I have listed the frequent ones.