大家一起学python-day3-for和while基础知识、嵌套和简单的字符串知识

#题外话：快捷键1.ctrl+y删除那一整行
# 题外话：快捷键1.ctrl+y删除那一整行
# 2.把那一行向下移动。shift+ctrl+向下
# 1.用while循环打印小星星
num = 1
while num <6:
    print('*'*num)
    num+=1
# 2.用while的嵌套循环打印小星星
now = 1
while now<=5:
    col = 1
    while col<=now:
        print('*',end='')
        col+=1
    print()
    now+=1
# 3.用while的嵌套循环打印九九乘法表
j = 1
while j <=9:
    i=1
    while i <=j:
        print('{}*{}={}'.format(i,j,i*j),end='\t')
        i+=1
    print()
    j+=1
# 4.for循环及其相关
4.1
a = 'tom'
for i in a:
    print(i)
print("程序结束了")
4.2
for i in range(0,100):
    print(i)
    print("当前的num值是",num)
# 4.3for else循环
for i in range(5):
    print(i)
else:#for执行完了，就会执行else
    print('执行完了')
print("程序结束了")
# 5.while循环和它的某些衍生
# 5.1
num = 1
while num <= 5:
    print("当前的num值是",num)
    if num ==3:
        break#若换成continue会无限循环
    num+=1
print("程序结束了...")
# 5.2
num= 0
while num<=5:
    num+=1
    if num==3:
        continue
print("程序结束了")