python——for循环的应用

for循环：
1，基础训练
方法一
例1
for i in (1,2,3,4,5,6,7,8,9,0):
    print('lpc')
    print(i)

元素列表：
(1,2,3,4,5,6,7,8,9,0):
for循环会对应匹配列表里每一个值，直到讲所有值循环完成结束



方法二
例1
for i in range(12,16):
   print(i)
结果就是12 13 14 15


例2
for i in range(0,10,2):
    print(i)
0-10,每次间隔2

例3
for a in range(10):
    for b in range(10):
        print('axiba',end='')   
    print()

2.加强训练
用for循环做三角形
一
for a in range(1,6):
    for b in range(i,6):
        print('# ',end='')   
    print()
# # # # # 
# # # # 
# # # 
# # 
# 

二
for a in range(0,6):
    for b in range(0,a):
        print(' ',end=' ')
    for b in range(a,6):
        print('# ',end='')   
    print()
# # # # # # 
  # # # # # 
    # # # # 
      # # # 
        # # 
          # 
三
for a in range(1,6):
    for b in range(6,i+1):
        print('# ',end='')   
    print()

# # # # 
# # # # 
# # # # 
# # # # 
# # # # 
四
for a in range(1,8):
    for b in range(1,a+1):
        print('* ',end='')
    for b in range(a,8):
        print('# ',end='')   
    print()
* # # # # # # # 
* * # # # # # # 
* * * # # # # # 
* * * * # # # # 
* * * * * # # # 
* * * * * * # # 
* * * * * * * # 

五
for i in range(1,10):
    for j in range(1,11-i):
        print(' ',end=' ')
    for j in range(1,i):
        print('@ ',end='  ')
    print()
for i in range(1,10):
    for j in range(1,i):
        print(' ',end=' ')
    for j in range(1,11-i):
        print('@ ',end='  ')
    print()
                @   
              @   @   
            @   @   @   
          @   @   @   @   
        @   @   @   @   @   
      @   @   @   @   @   @   
    @   @   @   @   @   @   @   
  @   @   @   @   @   @   @   @   
@   @   @   @   @   @   @   @   @   
  @   @   @   @   @   @   @   @   
    @   @   @   @   @   @   @   
      @   @   @   @   @   @   
        @   @   @   @   @   
          @   @   @   @   
            @   @   @   
              @   @   
                @   

六
for a in range(1,8):
    for b in range(1,a+1):
        print('# ',end='')   
    print()
# 
# # 
# # # 
# # # # 
# # # # # 
# # # # # # 
# # # # # # # 

七
for a in range(1,8):
    for b in range(a,8):
        print(' ',end=' ')
    for c in range(1,a):
        print('# ',end='')
    print()
            # 
          # # 
        # # # 
      # # # # 
    # # # # # 
  # # # # # # 

3.加强训练
用for循环做乘法口决表
方法一：
for i in range(1,10):
    for j in range(1,i+1):
        print(str(i)+"*"+ str(j)+"="+str(i*j),end=" ")
    print()

方法二：

for i in range(1,10):
    for j in range(1,i+1):
        print("%d*%1d=%2d" % (j,i,i*j) ,end=' ')
    print()

结果：

1*1=1 
2*1=2 2*2=4 
3*1=3 3*2=6 3*3=9 
4*1=4 4*2=8 4*3=12 4*4=16 
5*1=5 5*2=10 5*3=15 5*4=20 5*5=25 
6*1=6 6*2=12 6*3=18 6*4=24 6*5=30 6*6=36 
7*1=7 7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49 
8*1=8 8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64 
9*1=9 9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81