diff --git a/Java/SolutionA.java b/Java/SolutionA.java
new file mode 100644
index 0000000..41c7548
--- /dev/null
+++ b/Java/SolutionA.java
@@ -0,0 +1,19 @@
+package Java;
+
+public class SolutionA {
+    public int maxProfit(int[] prices) {
+        int finalSell = 0;
+        int finalBuy = Integer.MIN_VALUE;
+        int firstSell = 0;
+        int firstBuy = Integer.MIN_VALUE;
+
+        for (int quote : prices) {
+            finalSell = Math.max(finalSell, finalBuy + quote);
+            finalBuy = Math.max(finalBuy, firstSell - quote);
+            firstSell = Math.max(firstSell, firstBuy + quote);
+            firstBuy = Math.max(firstBuy, -quote);
+        }
+
+        return finalSell;
+    }
+}
\ No newline at end of file
diff --git a/Java/SolutionB.java b/Java/SolutionB.java
new file mode 100644
index 0000000..e687f7e
--- /dev/null
+++ b/Java/SolutionB.java
@@ -0,0 +1,21 @@
+package Java;
+
+public class SolutionB {
+    public int minPatches(int[] nums, int n) {
+        int patches = 0;
+        long smallestUncovered = 1;
+        int cursor = 0;
+
+        while (smallestUncovered <= n) {
+            if (cursor < nums.length && nums[cursor] <= smallestUncovered) {
+                smallestUncovered += nums[cursor];
+                cursor++;
+            } else {
+                patches++;
+                smallestUncovered *= 2;
+            }
+        }
+
+        return patches;
+    }
+}
\ No newline at end of file
diff --git a/Java/SolutionD.java b/Java/SolutionD.java
new file mode 100644
index 0000000..8abecfb
--- /dev/null
+++ b/Java/SolutionD.java
@@ -0,0 +1,13 @@
+public class SolutionD {
+    public String shortestPalindrome(String s) {
+        String t = new StringBuilder(s).reverse().toString();
+
+        for (int i = 0; i < t.length(); i++) {
+            if (s.startsWith(t.substring(i))) {
+                return t.substring(0, i) + s;
+            }
+        }
+
+        return t + s;
+    }
+}
\ No newline at end of file