CoT_Q_A_RL

playground.py

from typing import List, Dict, Tuple, Union, Optional

def largest_prime_factor(n: int):
    """Return the largest prime factor of n. Assume n > 1 and is not a prime.
    Q: What/How is a prime factor of n?
    A: A prime factor of n is a prime number that divides n.
    Q: What/how a number is not prime?
    A: A number is not prime if it has more than two factors.
    Examples:
    Q: 15
    A: 5

    Q: 27
    A: 3

    Q: 30
    A: 5
    """
    factor = 2
    # factor = 2, because 2 is the smallest prime number.
    while factor * factor <= n:
    # A: The last line is to make sure that factor is not bigger than the square root of n.
      if n % factor == 0:
    # A: The last line is to check if factor is a factor of n.
        n /= factor
    # A: The last line is to remove factor from n.
      else:
        factor += 1
    # A: The last line is to move on to the next factor.
    return n

def search(lst) -> int:
    """
    You are given a non-empty list of positive integers. Return the greatest integer that is greater than 
    zero, and has a frequency greater than or equal to the value of the integer itself. 
    The frequency of an integer is the number of times it appears in the list.
    If no such a value exist, return -1.
    Q: What/How non-empty list of positive integers?
    A: A list that has positive integers in it.
    Q: What/how is an integer which frequency is greater than or equal to the value of the integer itself?
    A: An integer which frequency is greater than or equal to the value of the integer itself is an integer 
    which appears in the list more than or equal to the value of the integer itself.

    Q: search([4, 1, 2, 2, 3, 1]) 
    A: 2
    Q: search([1, 2, 2, 3, 3, 3, 4, 4, 4])
    A: 3
    Q: search([5, 5, 4, 4, 4])
    A: -1
    """
# Code the first line of the previous function
    d = {}
    # The previous line is to create an empty dictionary.
    for i in lst:
    # The previous line is to loop through the list of integers.
    # Q: Why is that helpful to achieve the correct function implementation?
    # A: Because you need to go through every integer in the list to figure out the frequency of         each integer.
        if i in d:
      # Q: Why did you code the previous line?
      # A: Because if the integer has already appeared in the list, you will need to update the         frequency of that integer.
      # Q: Why is that helpful to achieve the correct function implementation?
      # A: Because you need to keep track of the frequency of each integer.
            d[i] += 1
        # Q: Why did you code the previous line?
        # A: Because we need to increment the frequency of that integer by 1.
        # Q: Why is that helpful to achieve the correct function implementation?
        # A: Because you need to keep track of the frequency of each integer.
        else:
            d[i] = 1
        # Q: Why did you code the previous line?
        # A: Because if the integer is the first time appeared in the list, we need to add the         integer to the dictionary, with the value of 1.
        # Q: Why is that helpful to achieve the correct function implementation?
        # A: Because you need to keep track of the frequency of each integer.
    result = -1
    # The previous line is to set the initial result as -1
    # Q: Why is that helpful to achieve the correct function implementation?
    # A: Because you need to have a integer as the result, and -1 is the integer that is less than       0.
    for i in d:
    # The previous line is to loop through the dictionary.
    # Q: Why is that helpful to achieve the correct function implementation?
    # A: Because you need to go through every integer in the dictionary to figure out the highest         integer greater than 0,
        # and has a frequency greater than or equal to the value of the integer itself.
        if i > 0 and d[i] >= i:
      # Q: Why did you code the previous line?
      # A: Because we need to figure out the highest integer greater than 0,
        # and has a frequency greater than or equal to the value of the integer itself.
            result = max(result, i)
        # Q: Why did you code the previous line?
        # A: Because we need to get the highest integer greater than 0, and has a frequency greater         than or equal to the value of the integer itself.
        # Q: Why is that helpful to achieve the correct function implementation?
        # A: Because you need to keep track of the highest integer greater than 0, and has a frequency       greater than or equal to the value of the integer itself.
    return result