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Java中關於i++與++i的問題
在《Java程序員麵試寶典》裏麵有提到i++這個部分，j++是一個依賴於java裏麵的“中間緩存變量機製”來實現的。通俗的說
++在前就是“先加後賦”(++j)
++在後就是“先賦後加”(j++)
package cn.xy.test;
public class TestPlus
{
private static int a()
{
int i = 10;
int a = 0;
a = i++ + i++;
// temp1 = i; 10
// i = i + 1; 11
// temp2 = i; 11
// i = i + 1; 12
// a = temp1 + temp2 = 21;
return a;
}
private static int b()
{
int i = 10;
int b = 0;
b = ++i + ++i;
// i = i + 1; 11
// temp1 = i; 11
// i = i + 1; 12
// temp2 = i; 12
// b = temp1 + temp2 = 23;
return b;
}
private static int c()
{
int i = 10;
int c = 0;
c = ++i + i++;
// i = i + 1; 11
// temp1 = i; 11
// temp2 = i 11
// i = i + 1; 12
// c = temp1 + temp2 = 22
return c;
}
private static int d()
{
int i = 10;
int d = 0;
d = i++ + ++i;
// temp1 = i; 10
// i = i + 1; 11
// i = i + 1; 12
// temp2 = i; 12
// d = temp1 + temp2 = 22;
return d;
}
public static void main(String[] args)
{
System.out.println(a());
System.out.println(b());
System.out.println(c());
System.out.println(d());
}
}
原帖地址:https://blog.csdn.net/zlqqhs/article/details/8288800
最後更新：2017-04-04 07:32:14