分考场

def solve(____):
    n = int(____)
    from collections import defaultdict
    graph = defaultdict(____)
    for r in relations.split(____):
        a, b = map(int, r.split(____))
        graph[a].add(____)
        graph[b].add(____)
    colors = [____] * (____)
    def can_color(____):
        for neighbor in graph[node]:
            if colors[neighbor] == color:
                return False
        return True
    def dfs(____):
        if node > n:
            return True
        for color in range(____, n + ____):
            if can_color(____):
                colors[node] = color
                if dfs(____):
                    return True
                colors[node] = ____
        return False
    dfs(____)
    print(max(____))