add 3216

Author: fishercoder1534

paginated_contents/algorithms/4th_thousand/README.md

@@ -1,5 +1,6 @@
 | #    | Title                                                                                                                                                               | Solutions                                                                                                                         | Video                                                                         | Difficulty | Tag                                                                  
 |------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------|------------|----------------------------------------------------------------------
+| 3216 | [Lexicographically Smallest String After a Swap](https://leetcode.com/problems/lexicographically-smallest-string-after-a-swap/)                                                                                       | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3216.java) |                                                                               | Easy       | Greedy
 | 3212 | [Count Submatrices With Equal Frequency of X and Y](https://leetcode.com/problems/count-submatrices-with-equal-frequency-of-x-and-y/)                                                                                       | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3212.java) |                                                                               | Medium     | Prefix Sum
 | 3211 | [Generate Binary Strings Without Adjacent Zeros](https://leetcode.com/problems/generate-binary-strings-without-adjacent-zeros/)                                                                                       | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3211.java) |                                                                               | Medium     | Recursion, Backtracking
 | 3210 | [Find the Encrypted String](https://leetcode.com/problems/find-the-encrypted-string/)                                                                                       | [Java](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/fourththousand/_3210.java) |                                                                               | Easy       |

src/main/java/com/fishercoder/solutions/fourththousand/_3216.java

@@ -0,0 +1,27 @@
+package com.fishercoder.solutions.fourththousand;
+
+public class _3216 {
+    public static class Solution1 {
+        public String getSmallestString(String s) {
+            for (int i = 0; i < s.length() - 1; i++) {
+                if (s.charAt(i) > s.charAt(i + 1) && sameParity(s.charAt(i), s.charAt(i + 1))) {
+                    char[] charArray = s.toCharArray();
+                    char tmp = charArray[i];
+                    charArray[i] = charArray[i + 1];
+                    charArray[i + 1] = tmp;
+                    return new String(charArray);
+                }
+            }
+            return s;
+        }
+
+        private boolean sameParity(char c1, char c2) {
+            int num1 = Integer.parseInt(c1 + "");
+            int num2 = Integer.parseInt(c2 + "");
+            if (num2 % 2 == 0 && num1 % 2 == 0 || (num2 % 2 == 1 && num1 % 2 == 1)) {
+                return true;
+            }
+            return false;
+        }
+    }
+}