1.
program HCN;
uses crt;
var cd,cr:longint;
begin
clrscr;
write('Nhap vao chieu dai ');readln(cd);
write('Nhap vao chieu rong ');readln(cr);
writeln('Chu vi HCN = ',(cd+cr)*2);
writeln('Dien tich HCN = ',cd*cr);
readln;
end. 
2.
program hinhtron;
uses crt;
var r:real;
begin
clrscr;
write('Nhap vao ban kinh = ');readln(r);
writeln('chu vi hinh tron = ',2*r*pi:0:2);
writeln('Dien tich hinh tron = ',r*r*pi:0:2);
readln;
end.

Program Typlex;

Uses crt;

Var a,b: real;

Begin

     Writeln('Chieu dai: '); Readln(a);

     Writeln('Chieu rong: '); Readln(b);

     Writeln('Chu vi: ',(a+b)*2:0:2);

     Writeln('Dien tich: ',a*b:0:2);

     Readln

End.

Program Typlex;

Uses crt;

Var r: real;

Begin

     Writeln('Ban kinh: ');readln(r);
     Writeln('Chu vi: ',2*r*pi:0:2);
     Writeln('Dien tich hinh tron: ',r*r*pi:0:2);

     Readln

End.

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