java的循环 while

一、while循环

package Java基础.循环while;

public class while循环出100 {
    public static void main(String[] args) {
        //输出1~100
        int i = 0;
        while (i<100){

            i++;
            System.out.println(i);
        }
    }
}

100以内的求和

package Java基础.循环while;

public class while求和 {
    public static void main(String[] args) {
        //计算1+2+3+。。。。
        int i=0;
        int sum =0;
        while (i<=100){
            sum = sum + i;
            i++;
        }
        System.out.println(sum);
    }
}

二、do- while 与 while的区别

public class dowhile循环 {
    public static void main(String[] args) {
        int a = 0;
        while (a<0){           //先判断后进入 ，可能不进入
            System.out.println(a);
            a++;
        }
        System.out.println("============================");
        do{                  //先进入后判断，至少进入一次
            System.out.println(a);
            a++;
        }while (a<0);
    }
}

m.out.println(a);
a++;
}while (a<0);
}
}

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