连接符

package com.changl.operator;

public class Demo07 {
    public static void main(String[] args) {
        int a = 10;
        int b = 20;

        a+=b;   //a = a+b

        System.out.println(a);

        //字符串连接符    + ， String
        System.out.println(""+a+b);     //字符串在前面转化为字符串
        System.out.println(a+b+"");     //字符串在后面先计算
    }
}
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