海伦公式

海伦公式

根据三角形的三条边长度a,b,c，计算三角形的面积S
p = (a + b + c)/2
S^2 = p * (p - a) * (p - b) * (p - c)

海伦公式的Python实现

#输入三条变边长分别赋值给a,b,c
a,b,c = eval(input("give three number separated by comma:"))

#判断给定的三条边是否能组成一个三角形
while not (a+b>c and a+c>b and b+c>a):
    print('pls give 3 nums once again!')
    a,b,c = eval(input("give three number separated by comma:"))

p = (a + b + c)/2
area = (p * (p - a) * (p - b) * (p - c)) ** 0.5
print('三角形的面积为：{0:9.3f}'.format(area))