def triangle(a,b,c):
  if a>0 and b>0 and c>0:
    if a+b>c and b+c>a and a+c>b:
      if a == b and b == c:
        return ("这是等边三角形")
      elif a == b or b == c or c == a:
        return("这是等腰三角形")
      else:
        return("这是不规则三角形")
    elif a+b==c or b+c==a or a+c==b:
      return("这是个直角三角形")
    else:
      return('这好像不是个三角形')
  else:
    return("请输入大于0的数字")

#Filename:Triangle
#Function:Judgment triangle
#Author:Judy
#Time:2018.9.26

a=int(input("Please input the first side:"))  #输入第一条边
b=int(input("Please input the second side:"))  #输入第二条边
c=int(input("Please input the third side:"))  #输入第三条边
if (a+b>c) and (a+c>b) and (b+c>a):        #判断是否是三角形
  if a==b==c:
    print("This is a equilateral triangle") #等边三角形
  elif (a==b or a==c or b==c):
    print("This is a isosceles triangle")  #等腰三角形
  elif (a*a+b*b==c*c) or (a*a+b*b==c*c) or (a*a+b*b==c*c):
    print("This is a right triangle")    #直角三角形
  else:
    print("This is a scalene triangle")   #不规则三角形
else :
  print("This isn't a triangle")       #不是三角形