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Page 470



		for (lastNum = 1; lastNum <= 7; lastNum++) { for (numToPrint = 1; numToPrint <= lastNum; numToPrint++) cout << numToPrint; cout << endl; }



		prints the following triangle of numbers.



		1 12 123 1234 12345 123456 1234567



		Although For statements are used most frequently for count-controlled loops, C++ allows you to write any While loop by using a For statement. To use For loops intelligently, you should know the following facts.



		1. In the syntax template, InitStatement can be the null statement, and Expression2 is optional. If Expression2 is omitted, there is no statement for the compiler to insert at the bottom of the loop. As a result, you could write the While loop



		while (inputVal != 999) cin >> inputVal;



		as the equivalent For loop



		for ( ; inputVal != 999; ) cin >> inputVal;



		2. According to the syntax template, Expression1the While conditionis optional. If you omit it, the expression 1 (meaning TRUE) is assumed.



		The loop



		for ( ; ; ) cout H << endl;



		is equivalent to the While loop

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