Simple C++ (OOPs) Programs

/* Program to enter two values and perform addition and multiplication operation*/

#include<iostream.h>
#include<conio.h>
main()
{
      int n1,n2,sum,mul;
      cout<<"\n Enter any two numbers";
      cin>>n1>>n2;
      sum=n1+n2;
      mul=n1*n2;
      cout<<"\n Sum of two numbers is "<<sum;
      cout<<"\n Multiplication of two numbers is "<<mul;
      getch();
}

/* Program to show addition and average of three (3) numbers*/

#include<iostream.h>

#include<conio.h>

main()

{

      int n1,n2,n3,sum;

      float av;

      cout<<"\n Enter any three numbers";

      cin>>n1>>n2>>n3;

      sum=n1+n2+n3;

      av=sum/3.0;

      cout<<"\n Sum of three numbers is "<<sum;

      cout<<"\n Average of three numbers is "<<av;

      getch();

      }

/* Program to enter length and breadth of rectangle and show its area*/

#include<iostream.h>

#include<conio.h>

main()

{

      int l,b;

      float ar;

      cout<<"\n Enter value of length and breadth";

      cin>>l>>b;

      ar=l*b;

      cout<<"\n Area is: "<<ar;

      getch();

      }

/* Program to enter base and height of the triangle and show its area*/

#include<iostream.h>

#include<conio.h>

main()

{

      float b,h,ar;

      cout<<"\n Enter height and base of triangle";

      cin>>h>>b;

      ar=0.5*h*b;

      cout<<"\n Area of triangle is: "<<ar;

      getch();

      }

/* Program to enter Item name and its quantity and calculate the price*/

#include<iostream.h>

#include<conio.h>

main()

{

      int itcd;

      float pr,qty,tamt;

      char itnm[10];

      cout<<"\n Enter the item code and name";

      cin>>itcd>>itnm;

      cout<<"\n Enter item's quantity(in Kg) and price";

      cin>>qty>>pr;

      tamt=qty*pr;

      cout<<"\n Code\tName\tQty.\tPrice\tT.Amount";

      cout<<"\n "<<itcd<<"\t"<<itnm<<"\t"<<qty<<"\t"<<pr<<"\t"<<tamt;

      getch();

      }

PRECAUTIONS

1. Use accurate header files as sometimes we entered getch(); but we don’t apply is header i.e.#include<conio.h>.
2. Never apply space in header files.
3. Never to apply ‘;’ after void main.
4. After declaring variables, cout and cin statements apply ‘;’ so as prevent program from syntax error.
5. Apply ‘;’ after getch().
6. Always close the brackets if you have started.