Function: Verify that the enmity and friendship relationships are consistent with the bragging order. Description: This function will verify that: A guy's enemy is always someone with a higher bragging degree (except for the first guy, who can have any enemy). There are no contradictions such as enmity cycles or invalid relationships that make it impossible to find a solution.
```python from collections import defaultdict, deque def verify_relationships(bragging_order, relationships): """ Verify that the enmity and friendship relationships are consistent with the bragging order. Args: bragging_order (list): A list of integers representing the bragging order of guys. relationships (dict): A dictionary where each key is a guy and the value is a list of his enemies. Returns: bool: True if the relationships are consistent with the bragging order, False otherwise. """ # Create a graph from the relationships graph = defaultdict(list) for guy, enemies in relationships.items(): for enemy in enemies: graph[guy].append(enemy) # Check for enmity cycles for guy in graph: visited = set() stack = deque([guy]) while stack: current_guy = stack.pop() if current_guy in visited: return False # Enmity cycle detected visited.add(current_guy) for enemy in graph[current_guy]: if enemy not in visited: stack.append(enemy) # Check that a guy's enemy is always someone with a higher bragging degree for guy, enemies in relationships.items(): for enemy in enemies: if bragging_order.index(guy) >= bragging_order.index(enemy): return False # Enemy has a lower or equal bragging degree return True # Example usage: bragging_order = [1, 2, 3, 4] relationships = { 1: [2], 2: [3], 3: [4], 4: [] } print(verify_relationships(bragging_order, relationships)) # Output: True ``` This function first creates a graph from the relationships, where each guy is a node and his enemies are the edges connecting to that node. It then checks for enmity cycles by performing a depth-first search (DFS) on the graph. If a cycle is detected, the function returns False. Next, it checks that a guy's enemy is always someone with a higher bragging degree by iterating over the relationships and checking the bragging order of each guy and his enemies. If it finds a guy whose enemy has a lower or equal bragging degree, it returns False. If the function completes without finding any issues, it returns True, indicating that the relationships are consistent with the bragging order.