3.
a = 1 b = a
a = 1 b = 1
a = a + 2*b
a = 3 b = 1
если a>2 (да, 3>2) то
c = 2*a
a = 3 b = 1 с = 6
4.
a = 2 b = 3
пока b>0 (да, 3>0) делать
b = b - 1
a = a*2 + 1
a = 5 b = 2
пока b>0 (да, 2>0) делать
b = b - 1
a = a*2 + 1
a = 11 b = 1
пока b>0 (да, 1>0) делать
b = b - 1
a = a*2 + 1
a = 23 b = 0
пока b>0 (нет, 0=0) цикл закончен
a = 23 b = 0
С1.
var a,b,c,p,s: real;
begin
readln (a,b,c);
p := (a + b + c)/2;
s := sqrt (p*(p-a)*(p-b)*(p-c));
writeln (s:0:5)
end.