chat

🔍

question:Nina loves to collect rare gems. She has a unique way to store her collection such that she can always easily find a specific gem. She arranges her gem collection in a linear sequence. Recently, she received a new batch of gems and she wants to insert them into her existing collection while maintaining some special order. Every gem has a unique integer value representing its rarity. Nina wants to keep the sequence sorted in non-decreasing order according to their rarity values. She would like you to process a series of insertion operations and immediately provide the position each new gem should be inserted to maintain the order. For each new gem, determine its 0-based index position in the current sequence where it should be inserted. # Input - The first line contains a single integer `n` (1 ≤ n ≤ 100,000) — the number of gems initially in her collection. - The second line contains `n` integers` a1, a2, ..., an` (1 ≤ ai ≤ 1,000,000) — the initial sequence of gem rarities in non-decreasing order. - The third line contains an integer `m` (1 ≤ m ≤ 50,000) — the number of new gems to insert. - The fourth line contains `m` integers `b1, b2, ..., bm` (1 ≤ bi ≤ 1,000,000) — the rarities of the new gems Nina received. # Output - Output `m` lines, each containing one integer — the 0-based index position where the corresponding new gem should be inserted into the initial sequence to maintain the non-decreasing order. # Example Input ``` 5 1 3 5 7 9 3 2 6 8 ``` Output ``` 1 3 4 ``` **Note:** For the input example, - The gem with rarity 2 should be inserted at position 1 (between 1 and 3). - The gem with rarity 6 should be inserted at position 3 (between 5 and 7). - The gem with rarity 8 should be inserted at position 4 (between 7 and 9).

answer:def find_insert_positions(initial_gems, new_gems): Returns a list of index positions where each new gem should be inserted into the initial sequence of gems to maintain non-decreasing order. :param initial_gems: List of integers representing the initial gems' rarities in non-decreasing order. :param new_gems: List of integers representing the new gems' rarities. :return: List of integers representing 0-based index positions for each new gem. from bisect import bisect_left positions = [] for gem in new_gems: position = bisect_left(initial_gems, gem) positions.append(position) return positions

question:You are given an integer n and a list of n integers. Your task is to find out whether it's possible to rearrange these integers into pairs such that the sum of each pair is an odd number. A pair (a, b) has an odd sum if and only if one of the elements is even, and the other is odd. The first line of input contains the integer n (1 ≤ n ≤ 1000). The second line contains a list of n integers a_i (-1000 ≤ a_i ≤ 1000). Output "YES" if the integers can be rearranged into pairs with an odd sum, otherwise output "NO". Examples: Input: 4 2 3 4 5 Output: YES Input: 3 1 2 3 Output: NO Input: 6 -1 -2 -3 -4 -5 -6 Output: YES Explanation: In the first example, we can form pairs (2, 3) and (4, 5) both of which have odd sums. In the second example, we cannot form pairs such that the sum is odd, as we are left with an unpaired number. In the third example, the pairs (-1, -2), (-3, -4), and (-5, -6) all sum to an odd number.

answer:def can_form_odd_sum_pairs(n, lst): Determine if the integers can be rearranged into pairs such that each pair has an odd sum. Parameters: n (int): The number of integers. lst (List[int]): The list of integers. Returns: str: "YES" if pairs can be formed, otherwise "NO". even_count = sum(1 for x in lst if x % 2 == 0) odd_count = n - even_count # To form pairs, we need an even number of total elements # and at least one even and one odd number to form a pair with an odd sum. if even_count > 0 and odd_count > 0 and even_count % 2 == odd_count % 2: return "YES" return "NO"

question:In a distant land, there is a peculiar sequence of letters forming a string. The string contains only two types of characters: 'A' and 'B'. The sequence follows a special rule: each 'A' can be easily transformed into a 'B', but a 'B' can only be transformed into an 'A' if it is the first character in the string. Given a string, determine if it's possible to transform the entire string into a sequence containing only 'A's by following the aforementioned rules. Write a function that, given a string, returns whether such a transformation is possible. The input will be a single line containing the string s (1 ≤ |s| ≤ 105) which consists solely of the characters 'A' and 'B'. Return "Yes" if the transformation is possible, otherwise return "No". # Examples: Input: ABAB Output: Yes Input: BA Output: No # Explanation: In the first example, the string "ABAB" can be transformed as follows: "BBAB" -> "BAAB" -> "AAAB" -> "AAAA". In the second example, the string "BA" cannot be transformed because the 'B' is not at the first position, and thus cannot be transformed into an 'A'.

answer:def can_transform_to_all_A(s): Given a string consisting of 'A' and 'B', determine if the string can be transformed into a string containing only 'A's following these rules: - 'A' can be transformed into 'B' anytime - 'B' can only be transformed into 'A' if it is the first character in the string. Parameters: s (str): Input string. Returns: str: "Yes" if it is possible to transform the string into all 'A's, otherwise "No" if not s or s[0] == 'A': return "Yes" return "No"

question:You are given a string representing an operation log of web page requests. Each request can either be a navigation to a new page or a back operation, which navigates back to the previous page. The log is given as a string consisting of uppercase Latin letters, where each letter represents the identifier of a page being navigated to, except for the letter "B", which represents a back operation. The log is processed from left to right. Determine the final page you will be on after processing the entire log. If at any point there is no previous page to go back to when a "B" appears, ignore that "B" operation. The first line contains a single integer n (1 le n le 10^5) — the length of the log. The second line contains a string of length n consisting of uppercase Latin letters and the letter "B". Output the identifier of the final page you end up on after processing the log. If you are not on any page, output "None". For instance, if the string is "ARBBBQ", the sequence of operations would be: 1. Navigate to 'A' 2. Navigate to 'R' 3. Back to 'A' 4. Back to the starting state (no previous page) 5. Navigate to 'B' 6. Navigate to 'B' 7. Push 'Q' on top of current state Final result: 'Q' (the last navigated page) If the string is "ABB", the sequence of operations would be: 1. Navigate to 'A' 2. Back to the starting state (no previous page) 3. Back to the starting state (no previous page) 4. Back to the starting state (no previous page) Final result: None (no page navigated)

answer:def final_page(n, log): Determines the final page after processing the sequence of operations. Parameters: n (int): Length of the log string. log (str): Sequence of page navigations and back operations. Returns: str: The identifier of the final page or "None" if no page is navigated. stack = [] for char in log: if char == 'B': if stack: stack.pop() else: stack.append(char) return stack[-1] if stack else "None"