Join us in this comprehensive tutorial where we explore a C++ solution to find the length of the longest substring without repeating characters. We explain each line of code, providing a step-by-step breakdown of the algorithm. Learn how to efficiently track the last occurrence of each character, update the left pointer to maintain a valid substring, and calculate the maximum length. Whether you're a beginner or an experienced programmer, this video will enhance your understanding of string manipulation and problem-solving skills.