var
a,b,c:integer;
s,p:real;
begin
write ('a=');
readln(a);
write ('b=');
readln (b);
write ('c=');
readln(c);
p:=(a+b+c)/2;
s:=sqrt(p*(p-a)*(p-b)*(p-c));
writeln ('S=',s);
readln
end.

VAR
 N,M:LongInt;
BEGIN
 Write('N= ');
 ReadLn(N);
 M:=1;
 Repeat
  M:=M*4;
 Until M>=N;
 If M=N then WriteLn('Yes!') else WriteLn('No!');
 ReadLn;
END.

Var a:array[1..1000,1..1000] of longint;
b:array[1..1000] of longint;
i,j,n,m,max,v:longint;
Begin
Writeln('Vvedite storony kvadrata'); {no comment}
Readln(n);
m:=n;
v:=0;
Writeln('Zapolnenie massiva');  {no comment}
For i:=1 to n do
For j:=1 to n do
Readln(a[i,j]);
max:=a[1,1];
For j:=1 to n do
For i:=1 to n do
begin
if a[j,i]>max
Then max:=a[j,i];
If n=m
then b[j]:=a[j,i];
end;
For i:=1 to j do
v:=v+b[i];
Writeln(v:2)  ;
Readln;
End.

Uses CRT;
Var a:array[1..1000,1..1000] of longint;
b:array[1..1000] of longint;
i,j,n,max,v:longint;
Begin
Writeln('Введите сторону квадрата');
Readln(n);
v:=0;
Writeln('Заполнение массива');
For i:=1 to n do
For j:=1 to n do
Readln(a[i,j]);
max:=a[1,1];
For j:=1 to n do
For i:=1 to n do
begin
if a[i,j]>max
Then max:=a[i,j];
b[j]:=max;
end;
For i:=1 to n do
v:=v+b[i];
Writeln(v:2);
for i:=1 to n do
begin
for j:=1 to n do
begin
Write(a[i,j],' ');
end;
Writeln;
end;
End.