문자열에서 두번째로 큰 수 찾기

Author: holmir97

SecondLargestDigitString.java

@@ -0,0 +1,50 @@
+import java.util.*;
+
+
+// my solution_USE list
+public class SecondLargestDigitString {
+    public int secondHighest(String s) {
+        StringBuffer str = new StringBuffer(s);
+        List<Integer> list = new ArrayList<>();
+        char tmp[] = new char[str.length()];
+
+        str.getChars(0,str.length(),tmp,0);
+
+        for (int i = 0; i < str.length(); i++) {
+            if (tmp[i] >= '0' && tmp[i] <= '9')
+                list.add(tmp[i]-'0');
+        }
+
+        List<Integer> resultList = new ArrayList<>();
+        list.sort(Comparator.reverseOrder());
+        for(int i = 0; i<list.size(); i++){
+            if(!resultList.contains(list.get(i)))
+                resultList.add(list.get(i));
+        }
+
+        if(resultList.size() <2)
+            return -1;
+        return resultList.get(1);
+    }
+
+}
+
+/* best solution_USE TREESET
+class Solution {
+    public int secondHighest(String s) {
+        if (s.length() == 1 || s == null)
+            return -1;
+        TreeSet < Integer > set = new TreeSet < Integer > ();
+        for (int i = 0; i < s.length(); i++) {
+            if (Character.isDigit(s.charAt(i)))
+                set.add(Integer.parseInt(String.valueOf(s.charAt(i))));
+        }
+
+        if (set.size() > 1) {
+            set.pollLast();
+            return set.pollLast();
+        } else return -1;
+
+    }
+}
+ */