Java选票统计程序无论投票情况如何始终输出平局该如何解决？

问题原因 #

你代码的核心错误是字符串比较方式不符合Java语法规则：

• Java中==用于String这类引用类型时，比较的是两个对象的内存地址是否相同，而非字符串内容是否相等
• 你通过inputs.next()拿到的用户输入字符串vote，和代码里的常量字符串"A"、"B"是存放在不同内存地址的对象，所以所有vote == "A"、vote == "B"的判断结果永远为false，voteA和voteB始终都是初始值0，最终只会触发平局逻辑

修正方案 #

把投票计数的判断逻辑替换为equals方法比较字符串内容即可，推荐将常量字符串写在equals前，避免空指针异常：

//VOTE COUNT 
Scanner inputs = new Scanner(System.in);

//getting total number of votes from user 
System.out.println("Enter the total number of votes in the election.");
int voteNum = inputs.nextInt();

//defining the two different votes for the two candidates
int voteA = 0;
int voteB = 0;

//collecting each vote one at a time from the user 
for (int i = 0; i < voteNum; i++) {
    System.out.println("Do you want to vote for candidate A or B? Enter A or B (Must be a capital letter).");
    String vote = inputs.next();
    // 修正字符串比较逻辑
    if ("A".equals(vote)) {
        voteA = voteA + 1;
    } else if ("B".equals(vote)) {
        voteB = voteB + 1;
    }
}

//displaying the final result of the election 
if (voteA > voteB) {
    System.out.println("The election winner is candidate A!");
} else if (voteB > voteA) {
    System.out.println("The election winner is candidate B!");
} else {
    System.out.println("Candidate A and candidate B have tied!");
}

内容的提问来源于stack exchange，提问作者Tia Rojas