One of the easiest leetcode question ? #computerscience #coding #leetcode #python

Introduction

In tackling the LeetCode question regarding the length of the last word in a string, we can develop a straightforward solution by following a systematic approach. The goal of this problem is to return the length of the last word present in the given string while considering spaces effectively.

Step-by-Step Solution

To begin, we need to create a variable—let's call it result—which will keep track of the length of the current word we are counting. As we traverse the string from the front, we will count each character belonging to the word. For example, if we encounter "Luffy," we find that it has five letters, therefore setting our result variable to five.

As we continue processing the string, we may encounter a space character. When this happens, it is essential to reset the result variable back to zero because it signals that we are either at the end of the current word or transitioning between words.

Next, we come across the word "Joy," followed by a space and then "boy." The word "boy" has three letters, leading our counter to six (for "Joy boy") as we disregard all space characters. However, if we then encounter extra spaces (like a space after "boy"), the result would reset to zero, which would be an incorrect output, as the correct final length should be calculated based on the last valid word.

To refine our approach, we introduce an additional variable named is_space. Each time we see a space character, we will toggle this variable. When we find a letter after a space, we'll check if is_space is true; if it is, we'll flip it back again and then reset our result to zero. This way, we preserve the length of the last valid word even in the presence of consecutive spaces after it.

In summary, this method dynamically adjusts to the structure of the input string, accurately tracking the length of the last word regardless of spacing complexities.

Keyword

• LeetCode
• length of last word
• string manipulation
• space character
• current word length
• result variable
• is_space variable
• toggle mechanism

FAQ

Q1: What is the main objective of the LeetCode question discussed?
A1: The main objective is to return the length of the last word in a given string, taking into account the spaces in the input.

Q2: Why do we need to reset the result variable?
A2: The result variable must be reset to zero when a space character is encountered to signify the end of the current word and the start of a new one.

Q3: How does the is_space variable help in solving the problem?
A3: The is_space variable helps track when we transition from spaces to letters, ensuring we do not reset the result after the last legitimate word has been counted, even if followed by spaces.

Q4: What should be done if there are consecutive spaces after the last word?
A4: If there are consecutive spaces, the is_space variable would prevent premature resetting of the result, allowing it to retain the correct length of the last word before the spaces.