a++ 與 ++a

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import org.junit.Test; /** * @author Jrtou * @since 2015/04/14 * * a++ 與 ++a * * 差異在先加和後加的觀念 */ public class Count { /** * a++ * 此方法print 列印出數值為 100 */ @Test public void count(){ int a = 100; System.out.println("Count"); System.out.println(a++); System.out.println(""); } /** * ++a * 此方法print 列印出數值為 101 */ @Test public void count2(){ int a = 100; System.out.println("Count2"); System.out.println(++a); System.out.println(""); } /** * a++ * 此方法print 列印出a數值為101 b數值為100 */ @Test public void count3(){ int a = 100; int b = a++; System.out.println("Count3"); System.out.println(b); System.out.println(a); System.out.println(""); } /** * ++a * 此方法print 列印出a數值為101 b數值為101 */ @Test public void count4(){ int a = 100; int b = ++a; System.out.println("Count4"); System.out.println(b); System.out.println(a); } }