uses crt;

var a,b:integer;

begin

clrscr;

readln(a,b);

writeln((a+b)*2);

writeln(a*b);

readln;

end.

Câu 2: 

#include <bits/stdc++.h>

using namespace std;

double a,b,cv,dt;

int main()

{

cin>>a>>b;

cv=(a+b)*2;

dt=a*b;

cout<<"Chu vi la:"<<fixed<<setprecision(2)<<cv<<endl;

cout<<"Dien tich la:"<<fixed<<setprecision(2)<<dt;

return 0;

}

Câu 1: 

#include <bits/stdc++.h>

using namespace std;

double a,b,c;

int main()

{

cin>>a>>b>>c;

cout<<fixed<<setprecision(2)<<(a+b+c)/3;

return 0;

}

nbbnbnbbnn\(\dfrac{^{ }}{ }\)

uses crt;

var a,b:real;

begin

clrscr;

readln(a,b);

writeln(2*(a+b):4:2);

writeln(a*b:4:2);

readln;

end.

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('Dien tich hinh chu nhat la:',S:3:2);  

   Writeln('Chu vi hinh chu nhat la:',CV:3:2);    

 readln;

end.

Program chunhat;

uses crt;

var a,b,p,s:real;

begin

clrscr;

writeln('Nhap chieu dai va rong cua hinh chu nhat: ');

readln(a,b);

s:=a*b;
p:=(a+b)*2;

write('Chu vi hinh chu nhat la: ', p:1:2);

writeln;

write('Dien tich hinh chu nhat la: ', s:1:2);

readln;

end.
 

Kết quả: 

#include <bits/stdc++.h>

using namespace std;

int a,b,dt;

int main()

{

cout<<"Nhap chieu dai: ";

cin>>a;

cout<<"Nhap chieu rong: ";

cin>>b;

dt=a*b;

cout<<"Dien tich la: "<<dt;

Return 0;

}

program hinh_chu_nhat;

uses crt;

var a,b:integer;

begin 

clrscr;

write('nhap gia tri cua chieu dai: ');readln(a);

write('nhap gia tri cua chieu rong: ');readln(b);
writeln('chu vi la: ',(a+b)*2);

write('dien tich la: ',a*b);

readln;

end.

a = int(input("Nhập chiều dài: "))

b = int(input("Nhập chiều rộng: "))

chu_vi = 2*(a+b)

dien_tich = a*b

print(f"Chu vi hình chữ nhật là: {chu_vi}")

print(f"Diện tích hình chữ nhật là: {dien_tich}")

#include <bits/stdc++.h>

using namespace std;

double a,b;

int main()

{

cin>>a>>b;

cout<<"Chu vi la: "<<fixed<<setprecision(2)<<(a+b)*2<<endl;

cout<<"Dien tich la: "<<fixed<<setprecision(2)<<a*b;

return 0;

}