*Chu vi hình vuông:

program CV_Hinh_vuong;

ues crt;

     var s, cv, a: real;

begin

      clrscr;

      writeln('Nhap chieu dai cua canh a: '); readln(a);

      cv:=a*4;

      writeln('Chu vi hinh vuong=', s:4*4);

      clrscr;

      writeln('Chu vi hinh chu nhat la: ', a*4);

      writeln('Dap so: ', a*4);

      readln

end.

*Chu vi hình chữ nhật: 

program CV_hinh_chu_nhat;

uses crt;

      var s, cv, a, b: real;

begin

      clrscr;

      writeln('Nhap chieu dai cua canh a: '); readln(a);

      writeln('Nhap chieu rong cua canh b: '); readln(b);

      cv:=(a+b)*2;

      clrscr;

      writeln('Chu vi hinh chu nhat la: ', (3+2)*2);

      writeln('Dap so: ', (3+2)*2);

      readln

end.

*Chu vi hình tròn:

program CV_hinh_tron;

uses crt;

      var  s, cv, r: real;

begin

      clrscr;

      writeln('Nhap chieu dai cua ban kinh r: '); readln(r);

      cv:2*r*pi;

      clrscr;

      writeln('Chu vi hinh tron la: ', 2*6*3.14);

      writeln('Dap so: ', 2*6*3.14);

      readln

end.

Program HINH_VUONG;

uses crt;

Var canh: real;

Begin

     clrscr;

     Write('Nhap do dai canh:');readln(canh);

     Writeln('Chu vi hinh vuong la:',4*canh:10:2)

readln

Program HINH_TRON;

uses crt;

Var r: real;

Begin

     clrscr;

     Write('Nhap ban kinh:'); readln(r);

     Writeln('Chu vi duong tron la:',2*pi*r:10:2);

readln

PROGRAM CHU_NHAT;

USES CRT;

VAR a, b, s, cv : REAL;

BEGIN

      WRITE(‘Nhap chieu dai:’); READLN(a);

      WRITE(‘Nhap chieu rong:’); READLN(b);

      s := a*b;

      cv := (a+b)*2;

WRITELN(‘Chu hin vi hinh chu nhat :’,cv:3:2);

      READLN;