double or one thing java solution - SALMA RUBI WABI

solutions/double-or-one-thing/Solution.java

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+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+public class Solution {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        int T = scanner.nextInt();
+        scanner.nextLine(); // Consume newline
+
+        for (int t = 1; t <= T; t++) {
+            String input = scanner.nextLine();
+            String output = getSmallestString(input);
+            System.out.println("Case #" + t + ": " + output);
+        }
+    }
+
+    private static String getSmallestString(String input) {
+        List<Pair<Character, Integer>> groupedInput = groupCharacters(input);
+        StringBuilder result = new StringBuilder();
+
+        for (int i = 0; i < groupedInput.size(); i++) {
+            Pair<Character, Integer> pair = groupedInput.get(i);
+            char current = pair.key;
+            int count = pair.value;
+
+            if (i < groupedInput.size() - 1 && current < groupedInput.get(i + 1).key) {
+                for (int j = 0; j < 2 * count; j++) {
+                    result.append(current);
+                }
+            } else {
+                for (int j = 0; j < count; j++) {
+                    result.append(current);
+                }
+            }
+        }
+
+        return result.toString();
+    }
+
+    private static List<Pair<Character, Integer>> groupCharacters(String input) {
+        List<Pair<Character, Integer>> groups = new ArrayList<>();
+        char currentChar = input.charAt(0);
+        int count = 1;
+
+        for (int i = 1; i < input.length(); i++) {
+            char c = input.charAt(i);
+            if (c == currentChar) {
+                count++;
+            } else {
+                groups.add(new Pair<>(currentChar, count));
+                currentChar = c;
+                count = 1;
+            }
+        }
+        groups.add(new Pair<>(currentChar, count)); // Add the last group
+        return groups;
+    }
+
+    private static class Pair<K, V> {
+        K key;
+        V value;
+
+        Pair(K key, V value) {
+            this.key = key;
+            this.value = value;
+        }
+    }
+}