python3(六) for while
# Python的循环有两种,一种是for...in循环,依次把list或tuple中的每个元素迭代出来 names = ['Michael', 'Bob', 'Tracy'] for name in names: print(name) # 计算1-10的整数之和 sumAdd = 0 for x in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]: sumAdd = sumAdd + x print(sumAdd) # python提供一个range()函数,可以生成一个整数序列,再通过list()函数可以转换为list。比如range(5)生成的序列是从0开始小于5的整数: print(list(range(5))) # [0, 1, 2, 3, 4] sum100 = 0 for x in range(101): sum100 = sum100 + x print(sum100) # while 计算100以内所有奇数之和 sumWhile = 0 n = 99 while n > 0: sumWhile = sumWhile + n n = n - 2 print(sumWhile) # break语句可以提前退出循环。 n = 1 while n <= 100: if n > 10: # 当n = 11时,条件满足,执行break语句 break # break语句会结束当前循环 print(n) n = n + 1 print('END') # 通过continue语句,跳过当前的这次循环,直接开始下一次循环 n = 0 while n < 10: n = n + 1 if n % 2 == 0: # 如果n是偶数,执行continue语句 continue # continue语句会直接继续下一轮循环,后续的print()语句不会执行 print(n)
补充-------------------------
你可以在循环内部使用break语句跳出循环,continue语句跳出本次循环
python for i in range(1, 10): if i == 5: break print(i) # Prints 1 2 3 4 for i in range(1, 10): if i == 5: continue print(i) # Prints 1 2 3 4 6 7 8 9
python for i in range(5): for j in range(3): print(i, j) # Prints # 0 0 # 0 1 # 0 2 # 1 0 # 1 1 # 1 2 # ...