11 while循环嵌套

# (1)打印十行十列小星星 (用两个循环)
 
 
print("<==>")
j = 0
while j<10:
 
    # 打印一行十个小星星
    i = 0
    while i<10:
        print("*",end="")
        i+=1
 
    # 控制换行
    print()
    j+=1
 
# 打印十行十列隔列换色小星星
‘‘‘外层行j动一次,里面列i动10次,外层动的慢,里层动的块‘‘‘
print("<==>")
j = 0
while j<10:
 
    # 打印一行十个小星星
    i = 0
    while i<10:
        # 控制打印星星的
        if i % 2 == 0:
            # 控制打印黑星
            print("★",end="")
        else:
            # 控制打印白星
            print("☆",end="")
        i+=1
 
    # 控制换行
    print()
    j+=1
 
 
# 打印十行十列隔行换色小星星
print("<==>")
j = 0
while j<10:
 
    # 打印一行十个小星星
    i = 0
    while i<10:
        # 控制打印星星的
        if j % 2 == 0:
            # 控制打印黑星
            print("★",end="")
        else:
            # 控制打印白星
            print("☆",end="")
        i+=1
 
    # 控制换行
    print()
    j+=1
     
     
# 99乘法表
# 方向一
i = 1
while i<=9:
 
    # 输出99乘法表
    j = 1
    while j<=i:
        print("%d*%d=%2d " % (i,j,i*j),end="")
        j+=1
     
    # 执行换行
    print()
     
    i+=1
# 方向二
print("<==>")
i = 9
while i>=1:
 
 
    # 输出99乘法表
    j = 1
    while j<=i:
        print("%d*%d=%2d " % (i,j,i*j),end="")
        j+=1
     
    # 执行换行
    print()
 
 
    i-=1
 
# 100~ 999 找吉利数字 111 222 123 321 888 ...
 
"""
n = 567
n // 100 => 5
n // 10 % 10 =>6
n % 10 => 7
"""
print(567 % 10)
# 方法一
i = 100
while i<=999:
    #百位
    baiwei = i // 100
    #十位
    shiwei = i // 10 % 10
    #个位
    gewei = i % 10
     
    if shiwei == gewei  and shiwei == baiwei :
        print(i)
     
    # 123 456
    if shiwei == gewei - 1 and shiwei == baiwei +1:
        print(i)
     
    # 654 987
    if shiwei == gewei+1 and shiwei == baiwei -1:
        print(i)
     
     
    i+=1
 
 
 
# ###百钱买百鸡  公鸡1块钱一只  母鸡 3块钱一只  小鸡5毛钱一只 100块钱 买 100只鸡 有多少种买法(经典题型)
"""
穷举法:一个一个试
a => (1,2)
b => (3,4)
c => (5,6)
a+b+c == 10?
 
1 3 5 
1 3 6
1 4 5 
1 4 6
2 3 5
2 3 6
2 4 5
2 4 6
x,y,z
x+y+z == 100 and  x + y*3+0.5*z = 100
"""
# x公鸡 y 母鸡 z小鸡
x = 0
while x <=100:
 
    y = 0
    while y<=33:
     
        z = 0
        while z<= 100:
         
            if (x+y+z == 100) and (x+y*3+0.5*z == 100):
                print(x,y,z)
            z+=1
     
        y+=1
 
    x+=1