C++ program to add two numbers

Here are the C++ programs to add two numbers .There are many different methods two add two numbers like add two numbers without using '+' operator or through recursion etc. Some of them are discussed below

Method 1 : C++ program to two add two numbers

#include<iostream>
using namespace std;
int main()
{
    int a,b,c;
    cout<<"Enter two numbers : ";
    cin>>a>>b;
    c=a+b;
    cout<<"Sum = "<<c<<endl;
    return 0;
}

Method 2 : C++ program to two add two numbers without using third variable

#include<iostream>
using namespace std;
int main()
{
    int a,b,c;
    cout<<"Enter two numbers : ";
    cin>>a>>b;
    a=a+b;
    cout<<"Sum = "<<a<<endl;
    return 0;
}

Method 3 : C++ program to two add two numbers using function

#include<iostream>
using namespace std;
int sum(int a,int b)
{
    return a+b;
}
int main()
{
    int a,b,c;
    cout<<"Enter two numbers : ";
    cin>>a>>b;
    c=sum(a,b);
    cout<<"Sum = "<<c<<endl;
    return 0;
}

Method 4 : C++ program to two add two numbers using pointers

#include<iostream>
using namespace std;
int main()
{
    int a,b,c;
    int *p,*q;
    p=&a;
    q=&b;
    cout<<"Enter two numbers : ";
    cin>>a>>b;
    c=*p+*q;
    cout<<"Sum = "<<c<<endl;
    return 0;
}

Method 5 : C++ program to two add two numbers using bitwise operators

#include<iostream>
#include<stdio.h>
#include<math.h>
using namespace std;
int main()
{
    int a,b,xo;
    cout<<"Enter the first number ";
    cin>>a;
    cout<<"Enter second number ";
    cin>>b;
    while(b)
    {
        xo=a^b;
        b=a&b;
        b<<=1;
        a=xo;
    }
    cout<<"Sum = "<<a;
    return 0;
}

Method 6 : C++ program to two add two numbers using recursion

#include<iostream>
using namespace std;
int sum(int a,int b)
{
    if(b==0)
    return a;
    sum(a+1,b-1);
}
int main()
{
    int a,b,c;
    cout<<"Enter two numbers : ";
    cin>>a>>b;
    c=sum(a,b);
    cout<<"Sum = "<<c<<endl;
    return 0;
}