
    In a social networking platform's friend recommendation system, given a user's interest profile represented as a binary number where each bit position corresponds to a specific interest category, write a function to activate (set to 1) the leftmost inactive interest category (0 bit) to expand the user's potential matching interests. The function should maintain the existing active interests while identifying and setting only the leftmost unset interest category.
    

    
def set_left_most_unset_bit(n):
    """
    In a social networking platform's friend recommendation system, given a user's interest profile represented as a binary number where each bit position corresponds to a specific interest category, write a function to activate (set to 1) the leftmost inactive interest category (0 bit) to expand the user's potential matching interests. The function should maintain the existing active interests while identifying and setting only the leftmost unset interest category.
    

    """
def set_left_most_unset_bit(n):
    """
    In a social networking platform's friend recommendation system, given a user's interest profile represented as a binary number where each bit position corresponds to a specific interest category, write a function to activate (set to 1) the leftmost inactive interest category (0 bit) to expand the user's potential matching interests. The function should maintain the existing active interests while identifying and setting only the leftmost unset interest category.
    

    """
    if not n & n + 1:
        return n
    (pos, temp, count) = (0, n, 0)
    while temp:
        if not temp & 1:
            pos = count
        count += 1
        temp >>= 1
    return n | 1 << pos