Python利用for循环打印星号三角形的案例

简单的for循环打印三角形

1，for循环方法实现星星三角

代码：

for i in range(0,5):

for j in range(i+1):
 if i == 4:
  print("* ",end="")
  continue
 if j == 0 or j == i:
  print("* ",end="")
 else:
  print(" ",end="")
print()

2.实心三角：

for i in range(5):
print("* " * (i+1))

3.实心正方形

for i in range(5):

print("* "*5)
print()

4.空心正方形

for i in range(5):

print("* "*5)
print()
for i in range(4):
if i == 0:
 print("* " * 5)
if i ==3:
 print("* " * 5)
 continue
for j in range(5):
 if j == 0:
  print("* ",end=" ")
 if j == 4:
  print("* ")
 else:
  print(" ",end="")

5.金字塔：

for i in range(5):

print(" "*(4-i),end="")
print(" * "*(i+1))

刚开始学习，博客写得不是很好。

补充知识：python:任意输入3个数,判断能否组成三角形

任意输入3个数,判断能否组成三角形,并输出三角形为等边/等腰/直角/普通三角形.

三角形:两边之和大于第三边

直角三角形:勾股定理

#!/usr/bin/python
# -*- coding:utf-8 -*-
#输入合法性检查,必须输入正数,不支持科学计数法
def ispositive(numb):
 try:
   float(numb)
 except:
   return False
 else:
   if float(numb) <= 0:
     return False
   else:
     return True
#直角三角形判断
def ispythagoras(a,b,c):
 if a**2 + b**2 == c**2 or a**2 + c**2 == b**2 or b**2 + c**2 == a**2:
   return True
 else:
   return False

num1 = input("pls enter 1st number:\n")
while not ispositive(num1):
 num1 = input("That's not a valid number. Try again:\n")

num2 = input("pls enter 2nd number:\n")
while not ispositive(num2):
 num2 = input("That's not a valid number. Try again:\n")

num3 = input("pls enter 3rd number:\n")
while not ispositive(num3):
 num3 = input("That's not a valid number. Try again:\n")

num1 = float(num1)
num2 = float(num2)
num3 = float(num3)
#欢迎点评,引用请注明出处
if num1 + num2 > num3 and num2 + num3 > num1 and num1 + num3 > num2:
 if num1 == num2 == num3:
   print("％.2f\n％.2f\n％.2f\n可以组成等边三角形" ％ (num1,num2,num3))
 elif num1 == num2 or num2 == num3 or num1 == num3:
   if ispythagoras(num1,num2,num3):
     print('％.2f\n％.2f\n％.2f\n可以组成等腰直角三角形' ％ (num1,num2,num3))
   else:
     print('％.2f\n％.2f\n％.2f\n可以组成等腰三角形' ％ (num1,num2,num3))
 elif ispythagoras(num1,num2,num3):
   print('％.2f\n％.2f\n％.2f\n可以组成直角三角形' ％ (num1,num2,num3))
 else:
   print('％.2f\n％.2f\n％.2f\n可以组成普通三角形' ％ (num1,num2,num3))
else:
 print('％.2f\n％.2f\n％.2f\n不能组成三角形' ％ (num1,num2,num3))

来源：https://blog.csdn.net/qq_39161804/article/details/81215754