program e1;
uses crt;
var x0,y0,x,y,r: real;
begin
readln(x0,y0,x,y,r);
if sqr(x-x0)+sqr(y-y0)<=r*r then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.


program e2;
uses crt;
var x,y: real;
begin
readln(x,y);
if (x>=0) and (x<=pi) and (y<=sin(x)) and (y>=0) then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.	

program e3;
uses crt;
var r1,r2,x,y,x0,y0,r: real;
begin
readln(x0,y0,x,y,r1,r2);
r:=sqr(x-x0)+sqr(y-y0);
if (r>=r1*r1) and (r<=r2*r2) then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.

Program e4;
uses crt;
var x,y: real;
begin
readln(x,y);
if (x>=-pi/2) and (x<=pi/2) and (y<=cos(x)) and (y>=0) then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.	

program e5;
uses crt;
var a: array [1..30] of integer; i, N: integer;
begin
readln(N);
a[1]:=1;
a[2]:=1;
for i:=3 to N do
a[i]:=a[i-2]+a[i-1];
for i:=1 to N do
write(a[i],' ');
repeat until keypressed
end.	


program e6;
uses crt;
var x,y: real;
begin
readln(x,y);
if (x>=0) and (x<=pi) and (y>=0) and (y<=abs(sin(2*x))) then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.

program e7;
uses crt;
var a: integer; b, n: longint;
begin
readln(n);
a:=(n)mod(5);
b:=(n)div(5);
if (a=1) or (a=3) then writeln((a+5)div(2)+b-1)
else writeln((a)div(2)+b);
repeat until keypressed;
end.	

program e8;
uses crt;
var a,b,c,d: real;
begin
readln(a,b,c,d);
if ((a=b) and (c=d)) or ((a=c) and (b=d)) or ((a=d) and (b=c))
then writeln('yes')
else writeln('no');
repeat until keypressed
end.	


program e9;
uses crt;
var a,b,c: real;
begin
readln(a,b,c);
if (a*a+b*b=c*c) or (a*a+c*c=b*b) or (b*b+c*c=a*a)
then writeln('yes')
else writeln('no');
repeat until keypressed
end.	


program e10;
uses crt;
var n,b:integer;
begin
readln(n);
b:=(n)mod(10);
if ((b>4) and (b<=9)) or (b=0) or (((n)div(10))=1) then writeln(n,' POKIB')
else if b=1 then writeln(n,' PIK')
else writeln(n,' POKU');
repeat until keypressed
end.	


Program e11;
uses crt;
 var
 c:char;
 begin
 readln(c);
 if ((c='Н')or (c='н')) then writeln ('"Називний" - "який?"') else
 if ((c='Р')or (c='р')) then writeln ('"Родовий" - "якого?"') else
 if ((c='Д')or (c='д')) then writeln ('"Давальний" - "якому?"') else
 if ((c='З')or (c='з')) then writeln ('"Знахідний" - "якого?"') else
 if ((c='О')or (c='о')) then writeln ('"Орудний" - "яким?"') else
 if ((c='М')or (c='м')) then writeln ('"Місцевий" - "(на) якому"') else
 if ((c='К')or (c='к')) then writeln ('"Кличний" - "який?"') else
 writeln ('error input');
 repeat until keypressed
 end.

Program e12;
uses crt;
 var
 c:char;
 begin
 readln(c);
 if ((c='Н')or (c='н')) then writeln ('"Називний" - "хто?", "що?"') else
 if ((c='Р')or (c='р')) then writeln ('"Родовий" - "кого?", "чого?"') else
 if ((c='Д')or (c='д')) then writeln ('"Давальний" - "кому?", "чому?"') else
 if ((c='З')or (c='з')) then writeln ('"Знахідний" - "кого?", "що?"') else
 if ((c='О')or (c='о')) then writeln ('"Орудний" - "ким?", "чим?"') else
 if ((c='М')or (c='м')) then writeln ('"Місцевий" - "(на) кому", "(на) чому?"') else
 if ((c='К')or (c='к')) then writeln ('"Кличний" - "хто?", "що?"') else
 writeln ('error input');
 repeat until keypressed
 end.


 Program e13;
 uses crt;
 var
 c:integer;
 begin
 readln(c);
 if ((c>=1) and (c<=3)) then writeln ('Початковий рівень') else
 if ((c>=4) and (c<=6)) then writeln ('Достатній рівень') else
 if ((c>=7) and (c<=9)) then writeln ('Середній рівень') else
 if ((c>=10) and (c<=12)) then writeln ('Високий рівень') else
 writeln ('error input');
 repeat until keypressed
 end.


Program e14;
 uses crt;
 var
 c:char;
 begin
 readln(c);
 case c of
 '1': writeln ('rasp 1'); 
 '2': writeln ('rasp 2');
 '3': writeln ('rasp 3'); 
 '4': writeln ('rasp 4'); 
 '5': writeln ('rasp 5'); 
 '6': writeln ('rasp 6'); 
 else
 writeln ('error input');
 end;
 repeat until keypressed
 end.

Program e15;
 uses crt;
 var
 c:char;
 begin
 readln(c);
 case c of
 '1': writeln ('Зима: Декабрь, Январь, Февраль'); 
 '2': writeln ('Весна: Март, Апрель, Май');
 '3': writeln ('Лето: Июнь, Июль, Август'); 
 '4': writeln ('Осень: Сентябрь, Октябрь, Ноябрь'); 
  else
 writeln ('error input');
 end;
 repeat until keypressed
 end.


 Program e16;
 uses crt;
 var
 c:integer;
 begin
 readln(c);
 if ((c>=1) and (c<=3)) then writeln ('"Перший квартал') else
 if ((c>=4) and (c<=6)) then writeln ('"другий квартал') else
 if ((c>=7) and (c<=9)) then writeln ('"Третій квартал') else
 if ((c>=10) and (c<=12)) then writeln ('"Четвертий квартал') else
 writeln ('error input');
 repeat until keypressed
 end. 


Program e17;
 uses crt;
 var
 c:integer;
 begin
 readln(c);
 case c of
 '1': writeln ('Январь, Февраль, Март'); 
 '2': writeln ('Апрель, Май, Июнь');
 '3': writeln ('Июль, Август, Сентябрь'); 
 '4': writeln ('Октябрь, Ноябрь, Декабрь'); 
  else
 writeln ('error input');
 end;
 repeat until keypressed
 end. 

Program e18;
 uses crt;
 var
 c:integer;
 begin
 readln(c);
 case c of
 '1': writeln ('Январь'); 
 '2': writeln ('Февраль');
 '3': writeln ('Март'); 
 '4': writeln ('Апрель'); 
 '5': writeln ('Май'); 
 '6': writeln ('Июнь');
 '7': writeln ('Июль'); 
 '8': writeln ('Август'); 
 '9': writeln ('Сентябрь'); 
 '10': writeln ('Октябрь');
 '11': writeln ('Ноябрь'); 
 '12': writeln ('Декабрь'); 
  else
 writeln ('error input');
 end;
 repeat until keypressed
 end.


Program e19;
Uses crt;
var x1,x2,x3,x4,x5,x6,x7,x8,y1,y2,y3,y4,y5,y6,y7,y8,l1,l2,d1,d2,s: double;
Begin
 Writeln ('x1,y1,x2,y2=');
 Readln(x1,y1,x2,y2);
 Writeln ('x3,y3,x4,y4=');
 Readln(x3,y3,x4,y4);
 Writeln ('x5,y5,x6,y6=');
 Readln(x5,y5,x6,y6);
 Writeln ('x7,y7,x8,y8=');
 Readln(x7,y7,x8,y8);
 d1:=sqrt(sqr(x2-x1)+sqr(y2-y1));
 d2:=sqrt(sqr(x3-x4)+sqr(y3-y4));
 l1:=sqrt(sqr(x5-x1)+sqr(y5-y1));
 l2:=sqrt(sqr(x6-x2)+sqr(y6-y2));
 s:=d1*d2;
 if ((d1*d1+d2*d2)=round(l1*l1)) and (l1=l2) then
         Writeln('Pryamougolnik, S=',s:5:3)
	else
              Writeln('Ne pryamougolnik');

  repeat until keypressed
 end.


Program e20;
uses crt;
var x,y: real;
begin
readln(x,y);
if (x>=-pi/2) and (x<=pi/2) and (y>=0) and (y<=abs(cos(2*x))) then
writeln('belongs')
else
writeln('doesnt belong');
repeat until keypressed
end.