The following program illustrates the usage and application of cin:

//Program 1.6
//This program demonstrates the usage
#include<iostream.h>
void main()
{
float fTemp;
float fCels;
cout<<"Enter the temperature in farenheit: ";
cin>>fTemp;
fCels = (fTemp - 32) * 5/9;
cout<<"The equivalent temperature in celsius is: "<<fCels<<endl;
}

The statement:

cin>>fTemp;

in the program causes the program to wait for the user to enter a value. This value is stored in the fTemp variable.

In Program 1.6 if the user enters 64, then the output of the program is:

The equivalent temperature in celsius is: 17.7778