This problem can be solved using the sliding window technique in linear time complexity. Here are the steps:

1. Initialize two pointers, `start` and `end`, to point to the first character of the string. Also, initialize a dictionary, `char_dict`, to keep track of the characters in the current substring and their indices.

2. Move the `end` pointer to the right one character at a time. For each character:

a. If the character is not in `char_dict`, add it to `char_dict` with its index as the value.

b. If the character is already in `char_dict`, it means we've found a repeating character. In this case, move the `start` pointer to the right of the repeating character's previous index in the string. Also, update the character's index in `char_dict`.

3. After each move of the `end` pointer, calculate the length of the current substring (i.e., `end - start + 1`) and update the maximum length if necessary.

4. Continue this process until the `end` pointer reaches the end of the string. The maximum length found is the length of the longest substring without repeating characters.

Here is a Python code snippet that implements these steps:

```python
def lengthOfLongestSubstring(s):
start = max_length = 0
char_dict = {}

for end in range(len(s)):
if s[end] in char_dict:
start = max(start, char_dict[s[end]] + 1)
char_dict[s[end]] = end
max_length = max(max_length, end - start + 1)

return max_length
```

This function returns the length of the longest substring without repeating characters in the input string `s`.

Question

This problem can be solved using the sliding window technique in linear time complexity. Here are the steps:

1. Initialize two pointers, `start` and `end`, to point to the first character of the string. Also, initialize a dictionary, `char_dict`, to keep track of the characters in the current substring and their indices.

2. Move the `end` pointer to the right one character at a time. For each character:

a. If the character is not in `char_dict`, add it to `char_dict` with its index as the value.

b. If the character is already in `char_dict`, it means we've found a repeating character. In this case, move the `start` pointer to the right of the repeating character's previous index in the string. Also, update the character's index in `char_dict`.

3. After each move of the `end` pointer, calculate the length of the current substring (i.e., `end - start + 1`) and update the maximum length if necessary.

4. Continue this process until the `end` pointer reaches the end of the string. The maximum length found is the length of the longest substring without repeating characters.

Here is a Python code snippet that implements these steps:

```python
def lengthOfLongestSubstring(s):
    start = max_length = 0
    char_dict = {}

for end in range(len(s)):
        if s[end] in char_dict:
            start = max(start, char_dict[s[end]] + 1)
        char_dict[s[end]] = end
        max_length = max(max_length, end - start + 1)

return max_length
```

This function returns the length of the longest substring without repeating characters in the input string `s`.

Knowee AI · Accepted Answer