推入堆栈char值具有不同的值

Question

大家。 我需要将char值放在Stack中：

        for(char ch: operand.toCharArray()) {
        System.out.println("ch: " + ch);
        numericsOfTheOperand.push((int) ch);
        System.out.println("numericsOfTheOperand.peek() " + numericsOfTheOperand.peek());
    }

例如，操作数：456454 控制台输出：

ch: 4
numericsOfTheOperand.peek() 52
ch: 5
numericsOfTheOperand.peek() 53
ch: 6
numericsOfTheOperand.peek() 54
ch: 4
numericsOfTheOperand.peek() 52
ch: 5
numericsOfTheOperand.peek() 53
ch: 4
numericsOfTheOperand.peek() 52
ch: 4
numericsOfTheOperand.peek() 52

我不明白为什么价值不同？ 我该如何解决？

Answer 1

要将char推送到Stack，您需要将其声明为：

Stack<Character> numericsOfTheOperand = new Stack<>();

然后你可以做你的事：

String operand = "456454";
for(char ch: operand.toCharArray()) {
    numericsOfTheOperand.push(ch);
    System.out.println("numericsOfTheOperand.peek() " + numericsOfTheOperand.peek());
}

输出：

numericsOfTheOperand.peek() 4
numericsOfTheOperand.peek() 5
numericsOfTheOperand.peek() 6
numericsOfTheOperand.peek() 4
numericsOfTheOperand.peek() 5
numericsOfTheOperand.peek() 4

您向char投了int，从而获得了int的价值。