【天梯】python L2-010 排座位 (25 point(s))

from collections import defaultdict
n,m,k=map(int,input().split())
friend=defaultdict(set)
dui=defaultdict(set)
for i in range(m):
    a,b,c=map(int,input().split())
    if c==1:
        friend[a].add(b)
        friend[b].add(a)
    else:
        dui[a].add(b)
        dui[b].add(a)
for i in range(k):
    a,b=map(int,input().split())
    flag=0
    if a in friend[b]:
        flag=1
    else:
        for j in friend[b]:
            if a in friend[j]:
                flag=2
                break
    if flag==1 and a not in dui[b]:
        print("No problem")
    elif flag==0 and a not in dui[b]:
        print("OK")
    elif flag==2 and a in dui[b]:
        print("OK but...")
    elif a in dui[b]:
        print("No way")