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Step 1: Start by including the necessary header file. In this case, we need the "iostream" file, which allows us to use input/output operations.

Step 2: Declare the main function. In C++, every program must have a main function, which serves as the entry point for the program.

Step 3: Inside the main function, declare any necessary variables. Variables are used to store data, and their types must be specified. For example, we can declare an integer variable named "num" to store a number.

Step 4: Use the "cin" object to read input from the user. In this case, we can use the "cin" object to read a value into the "num" variable.

Step 5: Perform any necessary calculations or operations using the variables. For example, we can square the value of "num" by multiplying it by itself.

Step 6: Use the "cout" object to display output to the user. In this case, we can use the "cout" object to display the squared value of "num" to the user.

Step 7: End the main function by returning a value. By convention, returning 0 indicates that the program executed successfully.

Step 8: End the program by closing any necessary resources. In C++, this is typically done automatically, so we don't need to include any specific code for this.