循环语句For While do-while的小练习

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/**

题目2：使用 for 、while 、do-while 语句编写程序，打印 1 到 100 的和

*/

class For{
	public static void main(String[] args){
		//定义整型变量sum，用来存和并初始化为0
		int sum = 0;
		for (int x = 1; x<=100; x++){
			sum = sum+x;
		}
			
		System.out.println("For: sum = "+sum);//输出1-100的和，格式为：For: sum = sum
	}
}

class While{
	public static void main(String[] args){
		//定义整型变量sum，用来存和并初始化为0
		int sum = 0;
		//定义整型变了x,初始化为1
		int x = 1;
		//当条件小于等于100时,执行下列循环语句
		while(x<=100){
			sum = sum+x;
			x++;
		}
		
		System.out.println("While: sum = "+sum);//输出1-100的和，格式为：While: sum = sum
	}
}

class DoWhile{
	public static void main(String[] args){
		//定义整型变量sum，用来存和并初始化为0
		int sum = 0;
		//定义整型变了x,初始化为1
		int x = 1;
		//执行循环语句
		do{
			sum = sum + x;
			x++;
		}
		//判断条件
		while(x<=100);
		
		System.out.println("D0_While: sum = "+sum);//输出1-100的和，格式为：D0_While: sum = sum
	}
}