今天学习的时while语句，代码如下：

package basic;

/**
 * **********************************************
 * This is the ninth code. Names and comments are followed original code strictly.
 * 
 * @author WX873
 ************************************************
 */
public class whileStatement {
	/**
	 * ******************************************
	 * The entrance of the program
	 * 
	 * @param args Not used now.
	 */
	public static void main(String args[]) {
		whileStatementTest();
	}//of main
	
	/**
	 * ******************************************
	 * The sum not exceeding a given value.
	 * ******************************************
	 */
	
	public static void whileStatementTest() {
		int tempMax = 100;
		int tempValue = 0;
		int tempSum = 0;
		
		//Approach 1
		while (tempSum <= tempMax) {
			tempValue ++;
			tempSum += tempValue;
			System.out.println("TempValue = " + tempValue + ", Tempsum = " + tempSum);
		}//of while
		tempSum -= tempValue;
		System.out.println("The sum not exceeding " + tempMax + " is " + tempSum);
		
		//Approach 2
		System.out.println("\r\nAlternative approach.");
		tempSum = 0;
		tempValue = 0;
		
		while (true) {
			tempValue ++ ;
			tempSum += tempValue ;
			System.out.println("TempValue = " + tempValue + ", Tempsum = " + tempSum);
			if (tempMax < tempSum) {
				break;
			}//of if
		}//of while
		tempSum -= tempValue;
		System.out.println("The sum not exceeding " + tempMax + " is " + tempSum);
	}//of whileStatementTest
}//of whileStatement

现在每天先读一下代码，然后自己尝试全部写出来。读代码的时候在想，第一种方法的条件如果改成tempSum < tempMax，是不是就不用回退。后来测试了一下，不是那样的。最后加上去的数导致tempSum大于tempMax，而跳出循环，而上一次执行了while语句，所以说要得到正确结果，必然要回退到上一步。