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program BRA5;
var  x2, x3, y1, y2, y3, a, b, c,  P: real;
I, t:integer;
q, y, n : char;
SS: ARRAY [1..20]     of real;
X:ARRAY [1..20] of real;
Begin
 
writeln(' y1, x2, y2, x3, y3');
 readln( y1, x2, y2, x3, y3);
Writeln('Vvedite kolichestvo elementov massiva');
 readln(t);
If t<0 then Writeln('Nedopustimoe kolichestvo elementov massiva');
writeln('Vvedite elementi massiva');
For i:=1 to t do begin
read(X [i]);
If (X[i]*y2 + x2*y3 + y1*x3 - x2*y1 - X[i]*y3 - x3*y2 = 0)
      then Writeln ('Nedopustimoe znachenie koordinat')
      else Begin
a:= sqrt((X[i]-x2)*(X[i]-x2) + (y1-y2)*(y1-y2));
b:= sqrt((x2-x3)*(x2-x3) + (y2-y3)*(y2-y3));
c:= sqrt((x3-X[i])*(x3-X[i]) + (y3-y1)*(y3-y1));
P:= (a + b + c) / 2;
SS[i]:= sqrt(P * (P-a) * (P-b) * (P-c));
end;
end;
y:= 'y';
n:= 'n';
while (q<>n) do begin
q:= y;
Writeln('vivesti result?');
   readln(q);
    If (q<>y) and (q<>n) then
    writeln('vvedite pravilno ');
      If q = y then begin
   writeln( 'vvedite nomer elementa') ;
      readln(i);
   IF i>t then writeln('vvedite pravilno') else begin
  writeln('X=', X[i]:3:5 , ' S=', SS[i]:3:5) ;
  If (X[i]>=0) and (x2>=0) and (x3>=0) and (y1>=0) and (y2>=0) and (y3>=0)
then Writeln ('v 1 kv. ')
else Writeln('ne v 1 kv. ');
end;
end;
end;
end.