Question

以下是我的代码。问题是找到给定字符串中的第一个唯一（不重复）字符，我是Java的初学者，所以现在我想知道如何调试代码......至于我有限的知识我甚至不知道如何开始调试......谢谢！

    public class Solution {
        public int firstUniqChar(String s) {
        //My idea without referring to any other solution.
        //put the all character into the hashmap, and delete the key if 
        //there is duplicate value, then get the first key of
        //the remaining map, that is the smallest index of the unique 
        //character;
        Map<Integer,Character> hmap=new HashMap<Integer,Character>();
            int index = 0;
            for (int i = 0; i < s.length(); i++){
                //int value=(int)((Integer)map.get(a[i]));
                char charI = s.charAt(i);
                index ++;
                hmap.put(index, charI);
                //Error: cannot find this method;
                while (hmap.ContainsValue(charI)){
                    hkey = charI.getkey();
                    hkey.remove();

                }
                }
        //to return the index of the first key in the hashmap.
        //Error: illegal start of type;
            return hmap.get(hmap.keySet().toArray()[0]);
        }
}

Answer 1

在此代码中，您将字符串s转换为char数组。从char数组中取一个char并将其与数组中的所有其他字符进行比较。如果找不到（除了它自己），你打破循环并打印它。这样您就可以在字符串中找到第一个唯一字符：

public static void main(String[] args) {

            String s = "abcd, afsfsfs, abcdef, 90> 20, abeds";
            char[] charArray = s.toCharArray();
            char current = 0;
            for (int i = 0; i < charArray.length; i++) {
                boolean contains = false;
                current = charArray[i];
                int j = 0;
                while (j < charArray.length) {
                    if (charArray[i] == charArray[j] && i != j) {
                        contains = true;
                        break;
                    }
                    j++;
                }
                System.out.println("current=" + current + " " + contains);
                if (j == charArray.length && !contains)
                    break;
            }
            System.out.println(current);
    }

打印：

current=a true
current=b true
current=c true
current=d true
current=, true
current=  true
current=a true
current=f true
current=s true
current=f true
current=s true
current=f true
current=s true
current=, true
current=  true
current=a true
current=b true
current=c true
current=d true
current=e true
current=f true
current=, true
current=  true
current=9 false
9

如何获得第一个独特的角色？

1 个答案: