Data commit

Task/Determine-if-a-string-has-all-unique-characters/Java/determine-if-a-string-has-all-unique-characters-1.java

@@ -0,0 +1,41 @@
+import java.util.HashMap;
+import java.util.Map;
+
+//  Title:  Determine if a string has all unique characters
+
+public class StringUniqueCharacters {
+
+    public static void main(String[] args) {
+        System.out.printf("%-40s  %2s  %10s  %8s  %s  %s%n", "String", "Length", "All Unique", "1st Diff", "Hex", "Positions");
+        System.out.printf("%-40s  %2s  %10s  %8s  %s  %s%n", "------------------------", "------", "----------", "--------", "---", "---------");
+        for ( String s : new String[] {"", ".", "abcABC", "XYZ ZYX", "1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ"} ) {
+            processString(s);
+        }
+    }
+
+
+
+    private static void processString(String input) {
+        Map<Character,Integer> charMap = new HashMap<>();
+        char dup = 0;
+        int index = 0;
+        int pos1 = -1;
+        int pos2 = -1;
+        for ( char key : input.toCharArray() ) {
+            index++;
+            if ( charMap.containsKey(key) ) {
+                dup = key;
+                pos1 = charMap.get(key);
+                pos2 = index;
+                break;
+            }
+            charMap.put(key, index);
+        }
+        String unique = dup == 0 ? "yes" : "no";
+        String diff = dup == 0 ? "" : "'" + dup + "'";
+        String hex = dup == 0 ? "" : Integer.toHexString(dup).toUpperCase();
+        String position = dup == 0 ? "" : pos1 + " " + pos2;
+        System.out.printf("%-40s  %-6d  %-10s  %-8s  %-3s  %-5s%n", input, input.length(), unique, diff, hex, position);
+    }
+
+}

Task/Determine-if-a-string-has-all-unique-characters/Java/determine-if-a-string-has-all-unique-characters-2.java

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+import java.util.HashSet;
+import java.util.List;
+import java.util.OptionalInt;
+import java.util.Set;
+
+public final class DetermineUniqueCharacters {
+
+	public static void main(String[] aArgs) {
+		List<String> words = List.of( "", ".", "abcABC", "XYZ ZYX", "1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ" );
+		
+		for ( String word : words ) {		
+			Set<Integer> seen = new HashSet<Integer>();
+	        OptionalInt first = word.chars().filter( ch -> ! seen.add(ch) ).findFirst();
+	        if ( first.isPresent() ) {	
+	            final char ch = (char) first.getAsInt();
+	            final String hex = Integer.toHexString(ch).toUpperCase();
+	            System.out.println("Word: \"" + word + "\" contains a repeated character.");
+	            System.out.println("Character '" + ch + "' (hex " + hex + ") occurs at positions "
+	            	+ word.indexOf(ch) + " and " + word.indexOf(ch, word.indexOf(ch) + 1));
+	        } else {
+	        	System.out.println("Word: \"" + word + "\" has all unique characters.");
+	        }
+	        System.out.println();			
+		}
+	}
+
+}