Question

how to declare input and output statement in c++

Answer 1

using cout<< for display("" in this double quotes you can display  anything) .

for an example

cout<<"hey!! how r you\n";

cin>> for input a value

Answer 2

Make sure you include the following header:

#include <iostream>

using namespace std;

Then you can utilize the statements:

cout << "String here" << endl;

cout << "endl breaks the line!";

and

cin >> variableName;

for storing values from keyboard input/buffer into variables. 

Note:  c-out = "console output" and c-in = "console input"