diff --git a/src/main/java/com/cool/hot100/binary_search/Num4.java b/src/main/java/com/cool/hot100/binary_search/Num4.java
new file mode 100644
index 0000000..8a41a9f
--- /dev/null
+++ b/src/main/java/com/cool/hot100/binary_search/Num4.java
@@ -0,0 +1,40 @@
+package com.cool.hot100.binary_search;
+
+import org.junit.Test;
+
+/**
+ * Created with IntelliJ IDEA.
+ *
+ * @Author: Cool
+ * @Date: 2024/09/15/23:15
+ * DayNumber 2
+ * Hard 3
+ * Level 8
+ */
+public class Num4 {
+    public double findMedianSortedArrays(int[] nums1, int[] nums2) {
+        int len1 = nums1.length;
+        int len2 = nums2.length;
+        int left=-1;
+        int right=-1;
+        int index1 = 0;
+        int index2 = 0;
+        for(int i=0;i<=(len1+len2)/2;i++){
+            left=right;
+            if(index1<len1&&(index2>=len2||nums1[index1]<nums2[index2])){
+                right=nums1[index1++];
+            }else{
+                right=nums2[index2++];
+            }
+        }
+        if(((len1+len2)&1)==0){
+            return (left+right)/2.0;
+        }else{
+            return right;
+        }
+    }
+    @Test
+    public void test(){
+        findMedianSortedArrays(new int[]{1,2},new int[]{3,4});
+    }
+}