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question:In a city, there are several bus routes available that connect various bus stops. Each route can be represented by pairs of connected stops and their travel times. However, there may be some routes which are redundant or lead to circular paths. You are given a list of stops and the routes that connect them, along with the travel time for each route. Your task is to process a list of requested journeys and determine the minimum travel time for each one. If a journey is not possible, output "IMPOSSIBLE". Each journey consists of a starting stop and a destination stop. -----Input----- The first line contains a positive integer S, the number of bus stops. The second line contains space-separated list of S strings, the names of the bus stops. All bus stop names are distinct. The third line contains a non-negative integer R, the number of available routes. Each of the next R lines describes one route and contains names B1 and B2 of two stops followed by a positive integer T, the travel time between the stops. It is guaranteed that B1 and B2 will be correct names of two different stops from the list of S stops given in the second line of the input file. For each pair of different stops, there is at most one route and each route will be described exactly once in the input file. Next line contains a positive integer Q, the number of queries for the shortest travel times. Each of the next Q lines contains names of two stops – the starting stop and the destination stop – for which you should find the shortest travel time. All strings in the input file are composed only of lowercase, uppercase letters of the English alphabet, and hyphens. Each string is non-empty and has a length of at most 20. If a line in the input file contains more than one element, consecutive elements on the line are separated by exactly one space. Each line of the input file has no leading or trailing spaces. -----Output----- For each query from the input file output a single line containing the minimum travel time or the word "IMPOSSIBLE" if the journey cannot be made. -----Constraints----- 1 <= S <= 50 0 <= R <= S * (S - 1) 1 <= T <= 20000 1 <= Q <= 50 1 <= length of each string <= 20 -----Example----- Input: 5 StopA StopB StopC StopD StopE 6 StopA StopB 10 StopB StopC 20 StopC StopD 15 StopD StopE 25 StopA StopC 30 StopA StopE 60 5 StopA StopD StopC StopE StopA StopE StopD StopA StopB StopA Output: 45 40 60 IMPOSSIBLE IMPOSSIBLE -----Explanation----- The first query can be completed by traveling StopA -> StopB -> StopC -> StopD with a total time of 45. The second query can be completed by traveling StopC -> StopD -> StopE with a total time of 40. The third query can be directly completed with a single route StopA -> StopE with a total time of 60. The fourth and fifth queries are not possible due to the direction of the routes, thus the output is "IMPOSSIBLE".

answer:import heapq def dijkstra(graph, start, goal): queue = [(0, start)] distances = {vertex: float('infinity') for vertex in graph} distances[start] = 0 while queue: current_distance, current_vertex = heapq.heappop(queue) if current_distance > distances[current_vertex]: continue for neighbor, weight in graph[current_vertex].items(): distance = current_distance + weight if distance < distances[neighbor]: distances[neighbor] = distance heapq.heappush(queue, (distance, neighbor)) return distances[goal] if distances[goal] != float('infinity') else "IMPOSSIBLE" def process_bus_routes(S, stops, R, routes, Q, queries): graph = {stop: {} for stop in stops} for route in routes: B1, B2, T = route graph[B1][B2] = T results = [] for query in queries: start, goal = query result = dijkstra(graph, start, goal) results.append(result) return results

question:John is interested in learning more about arrays and he came up with the following problem. John has an array of integers of size n. He can perform multiple operations to transform the array into another desired array. The operation he can perform is as follows: - Select any subarray (consecutive elements) of the current array. - In one operation, he can reverse the selected subarray. John wants to transform the initial array into the target array using the minimum number of operations. Write a program to determine the minimum number of operations required to achieve the transformation. Input The first line contains a single integer n (1 ≤ n ≤ 100) — the size of the array. The second line contains n integers a_1, a_2, ..., a_n — the elements of the initial array. The third line contains n integers b_1, b_2, ..., b_n — the elements of the target array. Output Print a single integer — the minimum number of operations required to transform the initial array into the target array. Examples Input 5 1 2 3 4 5 5 4 3 2 1 Output 1 Input 4 1 2 3 4 1 2 4 3 Output 1 Input 3 3 1 2 1 2 3 Output 2 Note In the first example, the initial array is [1, 2, 3, 4, 5] and the target array is [5, 4, 3, 2, 1]. John can achieve the transformation in one operation by reversing the entire array. In the second example, the initial array is [1, 2, 3, 4] and the target array is [1, 2, 4, 3]. John can achieve the transformation in one operation by reversing the subarray [3, 4]. In the third example, the initial array is [3, 1, 2] and the target array is [1, 2, 3]. John can achieve the transformation in two operations by reversing the subarray [1, 2] to get [3, 2, 1] and then reversing the entire array to get [1, 2, 3].

answer:def min_operations_to_transform(n, array_initial, array_target): This function returns the minimum number of operations required to transform the initial array into the target array by reversing any subarrays. # Edge case: if both arrays are already the same, no operation is needed. if array_initial == array_target: return 0 # Find the segments where the initial array and target array differ. l = 0 while l < n and array_initial[l] == array_target[l]: l += 1 r = n - 1 while r >= 0 and array_initial[r] == array_target[r]: r -= 1 # If the entire array is the same except for one continuous segment if array_initial[l:r+1] == array_target[l:r+1][::-1]: return 1 return 2 # Usage example n = 5 array_initial = [1, 2, 3, 4, 5] array_target = [5, 4, 3, 2, 1] print(min_operations_to_transform(n, array_initial, array_target)) # Output: 1

question:Write a program that simulates an elevator control system in a building. The building consists of several floors numbered from 1 to N (1-based index). The elevator can move between these floors according to the requests received. There are two types of requests: 1. "R x y" - A request to move a person from floor x to floor y. The elevator should move to floor x, pick up the person, and then move to floor y to drop them off. 2. "C z" - A request to move the elevator directly to floor z, regardless of its current state or position. Your task is to simulate these requests and output the sequence of floors that the elevator will visit in order. **Constraints** * The number of floors in the building 1 ≤ N ≤ 100 * The number of requests 1 ≤ Q ≤ 1000 * 1 ≤ x, y, z ≤ N **Input** The input consists of: 1. An integer N, the number of floors. 2. An integer Q, the number of requests. 3. Q lines, each containing one request in the format described above. **Output** Print the sequence of floors (separated by space) that the elevator visits in order. **Example** **Input** ```plaintext 5 5 R 1 3 R 3 5 C 2 R 2 4 R 4 1 ``` **Output** ```plaintext 1 3 3 5 2 2 4 4 1 ```

answer:def elevator_simulation(N, Q, requests): Given number of floors N, number of requests Q, and the list of requests, returns the sequence of floors the elevator will visit in order. current_floor = 1 # assume elevator starts at first floor sequence_of_floors = [] for request in requests: parts = request.split() if parts[0] == "R": x = int(parts[1]) y = int(parts[2]) sequence_of_floors.append(x) sequence_of_floors.append(y) elif parts[0] == "C": z = int(parts[1]) sequence_of_floors.append(z) return sequence_of_floors

question:You are given two arrays `A` and `B` of length `n`, each consisting of integers from 1 to n. Your task is to update the elements of array `A` by replacing each element `A[i]` with the minimum value of `A[i]` and `B[i]` for each index i from `1 to `n. Then determine the sum of the distinct values in the updated array `A`. -----Input----- The first line of the input contains an integer n (1 leq n leq 10^5). The next line contains n space-separated integers representing array `A`. The third line contains n space-separated integers representing array `B`. -----Output----- Output a single integer which is the sum of the distinct values in the updated array `A`. -----Examples----- Input 5 3 4 7 6 5 2 1 5 6 4 Output 10 Input 4 1 2 3 4 4 3 2 1 Output 10 -----Note----- In the first sample: - The updated array `A` will be: `[2, 1, 5, 6, 4]` - The distinct values are: `[2, 1, 5, 6, 4]` - The sum of the distinct values is 2 + 1 + 5 + 6 + 4 = 18 In the second sample: - The updated array `A` will be: `[1, 2, 2, 1]` - The distinct values are: `[1, 2]` - The sum of the distinct values is 1 + 2 = 3

answer:def sum_of_distinct_minimums(n, A, B): Updates elements of array A by replacing each element A[i] with min(A[i], B[i]) and returns the sum of the distinct values in the updated array A. # Update array A updated_A = [min(A[i], B[i]) for i in range(n)] # Convert to set to get distinct values and sum them distinct_values_sum = sum(set(updated_A)) return distinct_values_sum