Q.The code given below accepts N as an integer argument and returns the sum of all integers from 1 to N. Observe the following code carefully and rewrite it after removing all syntax and logical errors. Underline all the corrections made.

def Sum(N)  
   for I in range(N):  
       S=S+I  
   return S  
print(Sum(10)  

Concept: Variable initialization and correct loop range for summation.

Reasoning:

1. The variable S must be initialized to 0 before the loop begins; otherwise, S=S+I will raise a NameError in the first iteration. …

The problem asks us to identify and correct both syntax and logical errors in code meant to calculate the sum of integers from 1 to N. Understanding variable initialization and how Python's range() function works is the key.

Concept and intuition

1. Variable initialization. When you write S = S + I, Python first evaluates the right-hand side (S + I). If S was never assigned before, Python raises a NameError. An accumulator like S must be initialized to a starting value — 0 for a sum — before the loop.

2. Python's range() function.

   • range(stop) produces 0, 1, 2, ..., stop-1. So range(N) gives 0, 1, ..., N-1.
   • range(start, stop) produces start, ..., stop-1. So range(1, N+1) gives 1, 2, ..., N. The task is the sum from 1 to N, which must include N and start at 1, so range(N) is wrong here.

Errors and corrections

1. Missing colon after the function header: def Sum(N) must be def Sum(N):.
2. S not initialized: add S = 0 before the loop.
3. Wrong loop range: range(N) gives 0..N-1; change it to range(1, N + 1) to sum 1..N.
4. Missing closing parenthesis in the last line: print(Sum(10) must be print(Sum(10)). …