from turtle import *
from math import *
def kružnica(r):
    global x
    circle(r)
    lt(90); fd(r); rt(90)
    x = pos()
def tangenta(r,k):
    rt(90-k); fd(r); lt(90)
    color('blue')
    fd(2*r); bk(4*r); fd(2*r)
    write('t',font=('Arial',16,'bold'))
    rt(90); bk(r/2); pu(); lt(90); fd(15); pd() 
    color('Sienna')
    write('r',font=('Arial',16,'bold'))
    pu(); setpos(x); seth(90); pd()
   
def kružni_isjecak(r, kut1, kut2):
    while kut1<0 or kut1>=360:
        kut1 = textinput('Početni kut', 'kut1 = ')
        kut1 = int(kut1)
    while kut2<0 or kut2>=360:
        kut2 = textinput('Završni kut', 'kut2 = ')
        kut2 = int(kut2)
    color('black', 'yellow')
    begin_fill()
    seth(kut1);
    fd(r); lt(90)
    circle(r, kut2-kut1)
    lt(90); fd(r)
    end_fill()
    seth(90)
def opseg(r):
    o = round(2*r*pi,2)
    pu(); bk(25+r); pd()
    color('navy')
    write('o = '+str(o),font=('Arial',16,'bold'))
def površina(r):
    P = round(r*r*pi,2)
    pu(); bk(25); pd()
    color('indianred')
    write('P = '+str(P),font=('Arial',16,'bold'))
def kružni_odsjecak(r, kut1, kut2):
    while kut1<0 or kut1>=360:
        kut1 = textinput('Početni kut', 'kut1 = ')
        kut1 = int(kut1)
    while kut2<0 or kut2>=360:
        kut2 = textinput('Završni kut', 'kut2 = ')
        kut2 = int(kut2)
    pu(); setpos(x); pd();
    color('black', 'red')
    seth(kut1);
    pu(); fd(r); lt(90);pd()
    pocetak = pos()
    begin_fill()
    circle(r, kut2-kut1)
    setpos(pocetak)
    end_fill()
    seth(90)

title('Crtaj')
st(); lt(90);
r = textinput('Duljina polumjera', 'r = ')
r = int(r)
kružnica(r)
k = textinput('Kut', 'k = ')
k = int(k)
tangenta(r,k)
kut1 = textinput('Početni kut', 'kut1 = ')
kut1 = int(kut1)
kut2 = textinput('Završni kut', 'kut2 = ')
kut2 = int(kut2)
kružni_isjecak(r, kut1, kut2)
opseg(r)
površina(r)
kut3 = textinput('Početni kut', 'kut3 = ')
kut3 = int(kut3)
kut4 = textinput('Završni kut', 'kut4 = ')
kut4 = int(kut4)
kružni_odsjecak(r, kut3, kut4)