Introducing the for Loop

Circumstances often call upon a program to perform repetitive tasks, such as adding together the elements of an array one by one or printing some paean to productivity twenty times. The C++ for loop makes such tasks easy to do. Let's look at a loop in Listing 5.1, see what it does, and then discuss how it works.

Listing 5.1. forloop.cpp
// forloop.cpp -- introducing the for loop
#include <iostream>
using namespace std;
int main()
{
    int i;  // create a counter
    //   initialize; test ; update
    for (i = 0; i < 5; i++)
        cout << "C++ knows loops.\n";
    cout << "C++ knows when to stop.\n";
    return 0;
}

Here is the output:

 C++ knows loops. C++ knows loops. C++ knows loops. C++ knows loops. C++ knows loops. C++ knows when to stop. ...

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