python笔记01基础while，for

for遍历

    name = ''

    for x in name:
        print(x)
    else:
        print("没有数据")

九九乘法表

 i = 1
    while i<=9:
        j=1
        while j<=i:
            print("%d*%d=%-2d "%(j,i,i*j),end='')
            j+=1
        print('\n')
        i+=1