def introducere ():
    t=None
    a=int(input("\na="))
    b=int(input("\nb="))
    c=int(input("\nc="))
    t(a,b,c)
    return t
    triunghi=introducere()
    print(triunghi)

def validare(t):
    if len(t)!=3:
        return False
    if t[0]=<0 or t[1]=<0 or t[2]=<0:
        return False
    if t(0)+t(t)<t(2):
        return False
    if t(0)+t(2)<t(1):
        return False
    if t(1)+t(2)<t(0):
        return False
    return True
triunghi=citireTriunghi()
v=validare(triunghi)
if v==True:
    print ("Este triunghi")
else:
    print ("Nu este triunghi")

def echilateral (t):
    if t (0)==t(1) and t(1)==t(2):
        return True
    else:
        return False
def isoscel (t):
    if t(0)==t(1) or t(0)==t(2) or t(2)==t(1):
        return True
    else:
        return False

def dreptunghic (t):
    if t(0)*t(0)==t(1)*t(1)+t(2)*t(2):
        return True
    if t(1)*(t)==t(0)**t(0)+t(2)*t(2):
        return true
    return False

def tip (t):
    if echilateral(t)==True:
        return "echilateral"
    if isoscel(t)==True:
        return "isoscel"
    if dreptunghic(t)==True:
        return "dreptunghic"
    return "oarecare"
    t=tip(triunghi)
    print("triunghiul este {} este {}".format (triunghi,t))