Try–except execution flow in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of try-except with no error

What is the output of this code when no error occurs?

Python

try:
    print("Start")
    result = 10 / 2
    print("Result is", result)
except ZeroDivisionError:
    print("Division by zero!")
finally:
    print("End")

A Division by zero!\nEnd

B Start\nDivision by zero!\nEnd

C Start\nEnd

D Start\nResult is 5.0\nEnd

💡 Hint

Remember that except block runs only if an error occurs.

Since 10 divided by 2 is valid, no exception occurs. So the try block runs fully, printing 'Start' and 'Result is 5.0'. The finally block always runs, printing 'End'.

❓ Predict Output

intermediate

Output when exception occurs and is caught

What is the output of this code when a ZeroDivisionError occurs?

Python

try:
    print("Start")
    result = 10 / 0
    print("Result is", result)
except ZeroDivisionError:
    print("Division by zero!")
finally:
    print("End")

A Start\nDivision by zero!\nEnd

B Start\nResult is 0\nEnd

C Division by zero!\nEnd

D Start\nEnd

💡 Hint

Division by zero causes an exception, so except block runs.

The division by zero raises ZeroDivisionError, so the except block prints 'Division by zero!'. The finally block always runs, printing 'End'.

❓ Predict Output

advanced

Output with multiple except blocks

What is the output of this code?

Python

try:
    print("Start")
    x = int('abc')
    print("Parsed", x)
except ValueError:
    print("Value error caught")
except ZeroDivisionError:
    print("Zero division error caught")
finally:
    print("End")

A Start\nEnd

B Start\nValue error caught\nEnd

C Start\nParsed abc\nEnd

D Start\nZero division error caught\nEnd

💡 Hint

int('abc') raises ValueError.

Trying to convert 'abc' to int raises ValueError, so the first except block runs. The finally block always runs.

❓ Predict Output

advanced

Output when exception not caught

What happens when an exception is raised but not caught by except blocks?

Python

try:
    print("Start")
    x = [1, 2, 3]
    print(x[5])
except ZeroDivisionError:
    print("Zero division error caught")
finally:
    print("End")

A Start\nEnd\nIndexError exception raised

B Start\nZero division error caught\nEnd

C Start\nEnd

D IndexError exception raised

💡 Hint

IndexError is not caught by ZeroDivisionError except block.

Accessing x[5] raises IndexError, which is not caught. The finally block runs printing 'End'. Then the program raises IndexError.

🧠 Conceptual

expert

Order of execution in try-except-finally

Which option correctly describes the order of execution when an exception occurs inside the try block and is caught?

A finally block runs first, then try block, then except block

B except block runs first, then try block, then finally block

C try block runs until exception, except block runs, finally block runs

D try block runs fully, finally block runs, except block runs

💡 Hint

Think about what happens when an error occurs inside try.

When an exception occurs, the try block stops at the error, the except block runs to handle it, then the finally block runs always.