→ erspicu:我的個性並不會想打人家巴掌 都是同是 何必這樣 問題是 03/28 21:14
→ erspicu:好奇 這錯誤觀念到底是哪裡來的 以及 為何系統沒暴 03/28 21:14
※ 引述《erspicu (.)》之銘言：
: : The parts of an expression containing && or || operators are evaluated only
: : until it’s known whether the condition is true or false. Thus, evaluation
: : of the express
: : ( gender == FEMALE ) && ( age >= 65 )
: : stops immediately if gender is not equal to FEMALE (i.e., the entire
: : expression is false) and continues if gender is equal to FEMALE (i.e.,
: : the entire expression could still be true if the condition age >= 65 is true).
: : This feature of conditional AND and conditional OR expressions is called s
: : hort-circuit evaluation.
: || 如果前者為真,可以省略後算,直接回傳為真
: && 如果前者為偽,可以省略後算,直接回傳為偽
: 請搞清楚邏輯關係...
: 相反的 || 如果前者為偽,絕對不是像我同事說的,回傳為偽,省略後算
那你就巴掌文給他們開下去嘛:
public class test {
public static void main(String[] args) {
boolean a, b;
a = true; b = true;
System.out.println(a + " | " + b + " : " + (a | b));
System.out.println(a + " & " + b + " : " + (a & b));
a = true; b = false;
System.out.println(a + " | " + b + " : " + (a | b));
System.out.println(a + " & " + b + " : " + (a & b));
a = false; b = true;
System.out.println(a + " | " + b + " : " + (a | b));
System.out.println(a + " & " + b + " : " + (a & b));
a = false; b = false;
System.out.println(a + " | " + b + " : " + (a | b));
System.out.println(a + " & " + b + " : " + (a & b));
a = true; b = true;
System.out.println(a + " || " + b + " : " + (a || b));
System.out.println(a + " && " + b + " : " + (a && b));
a = true; b = false;
System.out.println(a + " || " + b + " : " + (a || b));
System.out.println(a + " && " + b + " : " + (a && b));
a = false; b = true;
System.out.println(a + " || " + b + " : " + (a || b));
System.out.println(a + " && " + b + " : " + (a && b));
a = false; b = false;
System.out.println(a + " || " + b + " : " + (a || b));
System.out.println(a + " && " + b + " : " + (a && b));
}
}
$~/code/Java$ javac test.java
$~/code/Java$ java test
true | true : true
true & true : true
true | false : true
true & false : false
false | true : true
false & true : false
false | false : false
false & false : false
true || true : true
true && true : true
true || false : true
true && false : false
false || true : true
false && true : false
false || false : false
false && false : false
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