diff --git a/day04/src/com/inmind/method01/Demo01.java b/day04/src/com/inmind/method01/Demo01.java
index ecc0796..f23b5dd 100644
--- a/day04/src/com/inmind/method01/Demo01.java
+++ b/day04/src/com/inmind/method01/Demo01.java
@@ -35,8 +35,9 @@ package com.inmind.method01;
  */
 public class Demo01 {
     public static void main(String[] args) {
-        int i;
-        i = getSum(10,20);//方法调用处
+        int a = 10;
+        int b = 20;
+        int i = getSum(a,b);//方法调用处
         System.out.println(i);//30
     }
 
diff --git a/day04/src/com/inmind/method01/Demo02.java b/day04/src/com/inmind/method01/Demo02.java
new file mode 100644
index 0000000..699d7fe
--- /dev/null
+++ b/day04/src/com/inmind/method01/Demo02.java
@@ -0,0 +1,50 @@
+package com.inmind.method01;
+
+public class Demo02 {
+    public static void main(String[] args) {
+        boolean result = isEqual(4, 4);
+        System.out.println(result);
+
+        int lh = getLH(10);
+        System.out.println(lh);
+
+        printN(5);
+
+    }
+    //案例1：比较两个整数是否相同
+    public static boolean isEqual(int a,int b){
+        //实现一
+        /*if (a == b) {
+            return true;
+        } else {
+            return false;
+        }*/
+
+        //实现二
+        /*boolean result = a==b? true:false;
+        return  result;*/
+
+//        return  a==b? true:false;
+
+        //实现三
+        return  a==b;
+    }
+
+    //案例2：运算1到n的累和
+    public static int getLH(int n) {
+        int result = 0;//累和
+        for (int i = 0; i <= n; i++) {
+            result += i;
+        }
+        return result;
+    }
+
+    //案例3：打印n遍HelloWorld.
+    public static void printN(int n){
+        for (int i = 0; i < n; i++) {
+            System.out.println("helloWorld");
+        }
+    }
+
+}
+