Overview

This problem asks us to determine which season a given month \(M\) belongs to and output the English name of that season. We can implement this using conditional branching according to the mapping given in the problem statement.

Analysis

Spring, Summer, and Autumn can each be represented as contiguous ranges of months as follows:

• Spring: \(3 \leq M \leq 5\)
• Summer: \(6 \leq M \leq 8\)
• Autumn: \(9 \leq M \leq 11\)

On the other hand, Winter consists of months \(12\), \(1\), and \(2\), split across the end and the beginning of the year. However, since the constraints guarantee that \(M\) is between \(1\) and \(12\), inclusive, we can conclude that if \(M\) does not fall into Spring, Summer, or Autumn, it must be Winter.

For this problem, a naive approach of directly checking the conditions from the problem statement is sufficiently fast. No special optimizations are required. However, be careful not to omit the boundaries of the ranges, as doing so would cause, for example, month \(5\) to not be recognized as Spring.

For example, when \(M = 7\), it satisfies \(6 \leq M \leq 8\), so we output Summer.

Algorithm

1. Read the integer \(M\) from the input.
2. Check the conditions in the following order and output the corresponding English name:
   • If \(3 \leq M \leq 5\), output Spring.
   • Otherwise, if \(6 \leq M \leq 8\), output Summer.
   • Otherwise, if \(9 \leq M \leq 11\), output Autumn.
   • Otherwise, output Winter.

By using if, elif, and else, we can ensure that exactly one matching season is output.

Complexity

• Time Complexity: \(O(1)\)
  The number of conditions checked is constant, regardless of the value of the month.
• Space Complexity: \(O(1)\)
  Aside from the variable used to store the input month, no significant memory is required.

Implementation Notes

• In Python, you can write 3 <= M <= 5 to test a range inclusive of both endpoints.

• Do not write the condition for Winter as 12 <= M <= 2. Since no integer satisfies this condition, we handle Winter using else in this approach.

• Be sure to match the case of the English names precisely as requested: Spring, Summer, Autumn, and Winter.

  Source Code

M = int(input())
if 3 <= M <= 5:
    print("Spring")
elif 6 <= M <= 8:
    print("Summer")
elif 9 <= M <= 11:
    print("Autumn")
else:
    print("Winter")

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This editorial was generated by gpt-6-astra-medium.