Program hinhchunhat;

Uses crt;

Var a,b:integer;

Begin

Clrscr;

Write('Nhap chieu dai va chieu rong:');

Readn(a,b);

Writeln('Chu vi HCN la:',(a+b)*2);

Writeln('Dien tich HCN la:',a*b);

Readln

End.

*******************

Program hinhtron;

Uses crt;

Var r:real;

Begin

Clrscr;

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

Writeln('Chu vi hinh tron la:',r*2*3.14);

Writeln('Dien tich hinh tron la:', r*r*3.14);

Readln

End.

*******************

Program hinhtamgiac;

Uses crt;

Var h,a:real;

Begin

Clrscr;

Write('Nhap chieu dai canh day:');

Readln(a);

Write('Nhap chieu cao:');

Readln(h);

Writeln('Dien tich hinh tam giac:',a*h/2:9:2);

Readln

End.

C1:

#include<iostream>
#include<conio.h>
using namespace std;
int main(){
    float chieudai,chieurong;
    cout<<"\n moi ban nhap chieu dai :";
    cin>>chieudai;
    cout<<"\n moi ban nhap chieu rong :";
    cin>>chieurong;
    cout<<"\n chu vi hinh chu nhat :"<<chuvi=(chieudai+chieurong)*2;
    cout<<"\n dien tich hinh chu nhat :"<<dientich=chieudai*chieurong;
         
    getch();
    return 0;

    }

C2:

#include<iostream>
#include<conio.h>
#define pi 3.14
using namespace std;
int main(){
    float r,chuvi,dientich;
    cout<<"\n moi ban nhap ban kinh r:";
    cin>>r;
    cout<<"\n chu vi hinh tron:"<<chuvi=2*pi*r;
    cout<<"\n dien tich hinh tron:"<<dientich=pi*r*r;
         
    getch();
    return 0;
    }

C3:

#include<iostream>
#include<conio.h>
#define pi 3.14
using namespace std;
int main(){
    float a,h;
    cout<<"\n moi ban nhap chieu cao h :";
    cin>>h;
    cout<<"\n moi ban nhap canh day a :";
    cin>>a;
    cout<<"\n dien tich hinh tam giac :"<<dientich=h*a/2;
         
    getch();
    return 0;
    }