Java利用for、while、do...while循环结构计算1~100的和

for循环：

public class ForZuoYeTest {
    public static void main(String[] args) {
        int sum = 0;
//定义变量，来承接
        for (int i = 1; i <= 100; i++) {
            sum += i;
        } System.out.println("和为：" + sum);
    }
}

while循环：

//与for循环相似
public class WhileZuoYeTest {
    public static void main(String[] args) {
        int sum = 0;
        int i = 1;
        while (i<=100){
            sum+=i;
            i++;
        }
        System.out.println("1~100的和为："+sum);
    }
}

 do...while循环：

public class Do_whileText {
    public static void main(String[] args) {
        int i = 1;
        int sum = 0;
        do {
            sum += i;
            i++;
        } while (i <= 100);
        System.out.println("1~100的和：" + sum);
    }
}