java 522.最长的罕见子序列II（第二）.java

Posted 2021-05-08

public class Solution {
    public int findLUSlength(String[] strs) {
        Arrays.sort(strs, new Comparator<String>(){
            public int compare(String a, String b) {
                return b.length() - a.length();
            }
        });
        int len = strs.length;
        for(int i = 0; i < len; i++){
            boolean isFound = true;
            for(int j = 0; j < len; j++){
                if (i != j) {
                    if (isSubSequence(strs[i], strs[j])) {
                        isFound = false;
                        break;
                    }
                    if (strs[i].length() > strs[i].length()) {
                        break;
                    }
                }
                
            }
            if (isFound) return strs[i].length();
        }
        return -1;
    }
    
    private boolean isSubSequence(String a, String b) {
        int lenA = a.length();
        int lenB = b.length();
        if (lenA > lenB) return false;
        if (lenA == lenB) return a.equals(b);
        int idx = 0;
        for (char c : b.toCharArray()) {
            if (idx < lenA && c == a.charAt(idx)) {
                idx++;
            }
        }
        return idx == lenA;
        
    }
}

public class Solution {
    public int findLUSlength(String[] strs) {
        int maxLen;
        Map<String, Integer> map = new HashMap<String, Integer>();
        for (String str : strs) {
            for (String seq : getSubSequence(str)) {
                map.put(seq, map.getOrDefault(seq, 0) + 1);
            }
            
        }
        int res = -1;
        for (Map.Entry<String, Integer> entry : map.entrySet()) {
            if (entry.getValue() == 1) {
                res = Math.max(res, entry.getKey().length());
            }
        }
        return res;
    }
    
    public Set<String> getSubSequence(String str) {
        Set<String> set = new HashSet<String>();
        if (str.length() == 0) {
            set.add("");
            return set;
        }
        Set<String> temp = getSubSequence(str.substring(1));
        set.addAll(temp);
        for (String seq : temp) {
            set.add(str.charAt(0) + seq);
        }
        return set;
    }
}

public class Solution {
    // https://discuss.leetcode.com/topic/85044/python-simple-explanation
    public int findLUSlength(String[] strs) {
        Arrays.sort(strs, new Comparator<String>() {
            public int compare(String s1, String s2) {
                return s2.length() - s1.length();
            }
        });
        int n = strs.length;
        for (int i = 0; i < n; i++) {
            String s1 = strs[i];
            boolean isFound = true;
            for (int j = 0; j < n; j++) {
                if (i != j && isSubSequence(s1, strs[j])) {
                    isFound = false;
                    break;
                }
            }
            if (isFound) {
                return s1.length();
            }
        }
        return -1;
    }
    private boolean isSubSequence(String s1, String s2) {
        if (s1.length() > s2.length()) return false;
        if (s1.length() == s2.length()) return s1.equals(s2);
        int index = 0;
        for (char c : s2.toCharArray()) {
            if (index < s1.length() && c == s1.charAt(index)) {
                index++;
            }
        }
        return index == s1.length();
    }
}

class Comparator1 implements Comparator<String>{
    public int compare(String a, String b){
        return -a.length() + b.length();
    }
}
public class Solution {
    public int findLUSlength(String[] strs) {
        Arrays.sort(strs, new Comparator1());
        for(int i = 0; i < strs.length; i++){
            String s = strs[i];
            int j = 0;
            for(j = 0; j < strs.length; j++){
                if(j==i) continue;
                String t = strs[j];
                if(s.length()> t.length()){
                    return s.length();
                }else if(s.length()== t.length()){
                    if(s.equals(t)) break;
                }else {
                    if(isSubstring(t, s)) break;
                }
            }
            if(j == strs.length) return s.length();
        }
        return -1;
    }
    
    public boolean isSubstring(String org, String sub){
        int idx = 0;
        for(int i = 0; i < sub.length(); i++){
            char c = sub.charAt(i);
            while(idx<org.length() && org.charAt(idx)!=c) idx++;
            if(idx==org.length()) return false;
            idx++;
        }
        return true;
    }
}