diff --git a/day4/U461920/fixed.cpp b/day4/U461920/fixed.cpp
index e69de29..753e5ab 100644
--- a/day4/U461920/fixed.cpp
+++ b/day4/U461920/fixed.cpp
@@ -0,0 +1,79 @@
+//fixed 暴力 11 points sub task 1
+
+#include<bits/stdc++.h>
+using namespace std;
+
+// #define DEBUG
+
+#ifdef DEBUG
+#define PRINT_ARRAY(a,size){cout<<#a<<" [";for(int i=1;i<=(size);i++){cout<<a[i]<<(i!=(size)?",":"]\n");}}
+#define PRINT_VALUE(v){cout<<#v<<" :"<<v<<endl;}
+#define PRINT_DEBUG(v){cout<<v<<endl;}
+#define DEBUG_CODE(v){v}
+#endif
+
+#ifndef DEBUG
+#define PRINT_ARRAY(a,size)
+#define PRINT_VALUE(v)
+#define PRINT_DEBUG(v)
+#define DEBUG_CODE(v)
+#endif
+
+const int MAX_N=5*1e5+5;
+int n;
+int a[MAX_N];
+int b[MAX_N];
+
+int compute_max_num(int b[],int size){
+    sort(b,b+size);
+    PRINT_ARRAY(b, size);
+    if (size==1) {
+        return 1;
+    }else if(size%2==0){
+        int mid1=b[size/2],mid1_num=0;
+        int mid2=b[size/2+1],mid2_num=0;
+
+        for (int i=1; i<=size; i++) {
+            if (mid1==b[i]) {
+                mid1_num++;
+            }else if(mid2==b[i]){
+                mid2_num++;
+            }
+        }
+        return max(mid1_num,mid2_num);
+    }else{
+        int mid=b[size/2+1];
+        int mid_num=0;
+        for(int i=1;i<=size;i++){
+            if (b[i]==mid) {
+                mid_num++;
+            }
+        }
+        return mid_num;
+    }
+}
+
+int check_every_sub(int a[],int size){
+    int ans=0;
+    for(int i=1;i<=size;i++){
+        for(int j=i;j<=size;j++){
+            for (int k=i; k<=j; k++) {
+                b[k-i+1]=a[k];
+            }
+            ans=max(ans,compute_max_num(b, j-i+1));
+        }
+    }
+    return ans;
+}
+
+int main(){
+    cin.sync_with_stdio(false);
+    cin.tie(0);
+
+    cin>>n;
+    for(int i=1;i<=n;i++){
+        cin>>a[i];
+    }
+
+    cout<<check_every_sub(a, n)<<endl;
+}
\ No newline at end of file