c++ - IF 语句中的多个 OR 或 AND 条件

Question

我对 IF 语句有一个基本的疑问。
假设我想将字符串 SUN 与字符数组(大小为 3)匹配。

if(arr[0]!='S' || arr[1]!='U' || arr[2]!='N')

cout << "no";

else

cout<< "yes";

是否在 If 语句中检查了所有条件，还是在第一次不匹配时返回 true？

如果所有条件都检查了，检查的顺序是从右到左吗？

Answer 1

根据 C++ 标准

1 The && operator groups left-to-right. The operands are both contextually converted to bool (Clause 4). The result is true if both operands are true and false otherwise. Unlike &, && guarantees left-to-right evaluation: the second operand is not evaluated if the first operand is false.

和

1 The || operator groups left-to-right. The operands are both contextually converted to bool (Clause 4). It returns true if either of its operands is true, and false otherwise. Unlike |, || guarantees left-to-right evaluation; moreover, the second operand is not evaluated if the first operand evaluates to true.