满足以下3个条件的4位数有多少个()
条件1: 不能包含4和9
条件2: 4位数字都不同
条件3: 奇数
cnt = 0 for i in range(1000, 10000): a = i % 10 if a % 2 == 0: continue b = int(i / 10) % 10 c = int(i / 100) % 10 d = int(i / 1000) % 10 if a != b and a != c and a != d and b != c and b != d and c != d and (a != 4 and a != 9 and b != 4 and b != 9 and c != 4 and c != 9 and d != 4 and d != 9 and d != 0): # print('a=', a, ', b=', b, ',c=', ',d=', d) cnt += 1 print(cnt)