What is wrong in it. Please explain

Question

#include <iostream>
using namespace std;

int main()
{
int a ;
int b ;
int sum = a + b;
cout <<"the sum of a+b is";
cin>>sum;
cout << sum;

return 0;
}

Answer 1

Cin means character input
Cout means character output

So you print "the sum of a+b" as a string then cin takes the value of sum and then cout prints the value of sum

Answer 2

D_Stark, AJAY gurjar you may think of cin as character in, and cout as character out, but officially:

cin means console input
cout means console output

Answer 3

What is cin

Answer 4

You're adding a and b without assigning any values to them. Being local variables, they will contain unknown values. I presume you meant to use cin with a and b rather than sum.

E.g.
int a, b;
cin >> a >> b;
int sum = a + b;
cout << "the sum of a + b is " << sum;