line = [int(x) for x in input().split(" ")] orok = [] esetek = [] for x in range(line[0]): line2 = [int(x) for x in input().split(" ")] orok.append({"x":line2[0],"y":line2[1]}) for x in range(line[1]): line2 = [int(x) for x in input().split(" ")] esetek.append({"x":line2[0],"y":line2[1]}) print(orok,esetek) distance = [int()] for j in esetek: min_distance = [10000000] for n in orok: if abs(j["x"] - n["x"]) >= abs(j["y"] - n["y"]): distance[0] = abs(n["x"] - j["x"]) else: distance[0] = abs(n["y"] - j["y"]) if distance[0] < min_distance[0]: min_distance = distance.copy() print(min_distance[0])