diff --git a/build.gradle.kts b/build.gradle.kts
index 818ae5b..841b95c 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -28,4 +28,12 @@ java {
 tasks.test {
     useJUnitPlatform()
     jvmArgs = listOf("-Dfast=true")
+}
+
+tasks.register("runPerformanceAnalyze", JavaExec::class.java)
+tasks.named<JavaExec>("runPerformanceAnalyze") {
+    dependsOn("testClasses")
+    group = "verification"
+    classpath = sourceSets.test.get().runtimeClasspath
+    mainClass.set("com.cleverthis.interview.PerformanceAnalyze")
 }
\ No newline at end of file
diff --git a/src/test/java/com/cleverthis/interview/PerformanceAnalyze.java b/src/test/java/com/cleverthis/interview/PerformanceAnalyze.java
new file mode 100644
index 0000000..6c3b089
--- /dev/null
+++ b/src/test/java/com/cleverthis/interview/PerformanceAnalyze.java
@@ -0,0 +1,47 @@
+package com.cleverthis.interview;
+
+import com.cleverthis.interview.padlock.PadlockImpl;
+
+/**
+ * Performance test but not mean to run in unit test.
+ */
+public class PerformanceAnalyze {
+    private static void solve(PadlockImpl padlock) {
+        // TODO
+    }
+
+    private static final String RUN_NAME = "Boilerplate";
+    private static final int TOTAL_RUN = 50;
+    private static final int NUMPAD_SIZE = 7;
+
+    static {
+        System.out.println("Run name: " + RUN_NAME);
+        System.out.println("Total run: " + TOTAL_RUN);
+        System.out.println("Numpad size: " + NUMPAD_SIZE);
+    }
+
+    public static void main(String[] args) {
+        long timeSum = 0;
+        long writeSum = 0;
+        for (int i = 0; i < TOTAL_RUN; i++) {
+            PadlockImpl padlock = new PadlockImpl(NUMPAD_SIZE);
+            padlock.resetCounter();
+            long start = System.currentTimeMillis();
+            solve(padlock);
+            long end = System.currentTimeMillis();
+            if (!padlock.isPasscodeCorrect()) throw new IllegalStateException(
+                    "Invalid solution: passcode not correct after return");
+            long dT = end - start;
+            timeSum += dT;
+            writeSum += padlock.getWriteCounter();
+            System.out.println("Run #" + (i + 1) + ": time: " + dT + "ms; write: " + padlock.getWriteCounter());
+        }
+        System.out.println("Run time sum: " + timeSum + "ms");
+        System.out.println("Write sum: " + writeSum);
+        double avgTime = timeSum / (double) TOTAL_RUN;
+        double avgWrite = writeSum / (double) TOTAL_RUN;
+        System.out.println("Avg run time: " + avgTime + "ms");
+        System.out.println("Avg write: " + avgWrite);
+        System.out.println("Calculated estimate avg run time: " + (avgTime / 1000 + avgTime) + "s");
+    }
+}
diff --git a/src/test/java/com/cleverthis/interview/SolutionTest.java b/src/test/java/com/cleverthis/interview/SolutionTest.java
index 64a0cdc..26eaf92 100644
--- a/src/test/java/com/cleverthis/interview/SolutionTest.java
+++ b/src/test/java/com/cleverthis/interview/SolutionTest.java
@@ -1,30 +1,13 @@
 package com.cleverthis.interview;
 
 import com.cleverthis.interview.padlock.PadlockImpl;
-import org.junit.jupiter.api.Test;
-
-import java.util.Random;
-
-import static org.junit.jupiter.api.Assertions.*;
 
 /**
  * This is a simple placeholder to show how unit test works.
- * You can replace it with your own test.
  */
-class SolutionTest {
-    private void solve(PadlockImpl padlock) {
+class SolutionTest extends SolutionTestBase {
+    @Override
+    protected void solve(PadlockImpl padlock) {
         new Solution().solve(padlock);
     }
-
-    @Test
-    void verify(){
-        Random random = new Random();
-        PadlockImpl padlock = new PadlockImpl(random.nextInt(1, 8));
-
-        long startTime = System.currentTimeMillis();
-        solve(padlock);
-        long endTime = System.currentTimeMillis();
-        assertTrue(padlock.isPasscodeCorrect());
-        System.out.println("Time usage: " + (endTime - startTime) + "ms");
-    }
 }
\ No newline at end of file
diff --git a/src/test/java/com/cleverthis/interview/SolutionTestBase.java b/src/test/java/com/cleverthis/interview/SolutionTestBase.java
new file mode 100644
index 0000000..cbe86e5
--- /dev/null
+++ b/src/test/java/com/cleverthis/interview/SolutionTestBase.java
@@ -0,0 +1,30 @@
+package com.cleverthis.interview;
+
+import com.cleverthis.interview.padlock.PadlockImpl;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * This is a base class for verifying the correctness of the solution.
+ */
+public abstract class SolutionTestBase {
+    
+    /**
+     * Implement your solution in this function.
+     * */
+    protected abstract void solve(PadlockImpl padlock);
+
+    protected void verify(int numpadSize) {
+        PadlockImpl padlock = new PadlockImpl(numpadSize);
+        solve(padlock);
+        assertTrue(padlock.isPasscodeCorrect());
+    }
+
+    @Test
+    void verify1to7() {
+        for (int i = 1; i <= 7; i++) {
+            verify(i);
+        }
+    }
+}