//表达式计算顺序都是从左到右 System.out.println(3 + 5 + " hello"); //8 hello System.out.println("hello " + 3 + 5); //hello 35 int a = 3; int b[] = new int[5]; b[a] = a = 6; //相当于b[3] = 6; for(i = 0; i < b.length; i++) { System.out.println(b[i]); } a = 6; a += (a = 9); System.out.println(a); //15 a = 6; a = a + (a = 9); System.out.println(a); //15 a = 6; int c = (a = 3) * a; System.out.println(c); //9
//不要在单个的表达式中对相同的变量赋值超过一次。 int j = 0; for (i = 0; i < 100; i++) j = j++; System.out.println(j); //0