diff --git a/day10/U178578/U178578.cpp b/day10/U178578/U178578.cpp
index e69de29..887f90f 100644
--- a/day10/U178578/U178578.cpp
+++ b/day10/U178578/U178578.cpp
@@ -0,0 +1,68 @@
+#include<bits/stdc++.h>
+using namespace std;
+#define int long long
+
+struct Node{
+    int k,x,q;
+    // bool isdone;
+};
+
+const int MAX_N=5e5+5;
+int n,q;
+int a[MAX_N],/*x[MAX_N],k[MAX_N],*/ans[MAX_N],xdir[MAX_N];
+Node nodes[MAX_N];
+int pn=0,p1=1;
+int readint();
+
+signed main(signed argc,char *argv[]){
+    n=readint();
+    for(int i=1;i<=n;i++){
+        a[i]=readint();
+        xdir[a[i]]=i;
+    }
+    q=readint();
+
+    for(int i=1;i<=q;i++){
+        int k = readint(),x=readint();
+        // k[i]=readint();
+        // x[i]=readint();
+        nodes[++pn]={k,x,i};
+    }
+    sort(nodes+1,nodes+pn+1,[](Node a,Node b)->bool{
+        return a.k<b.k;
+    });
+    pn++;
+    for(int i=1;i<=n-1;i++){
+        for(int j=1;j<=n-1-i;j++){
+            if(a[j]>a[j+1]){
+                xdir[a[j]]=j+1;
+                xdir[a[j+1]]=j;
+                swap(a[j],a[j+1]);
+            }
+        }
+        if(p1==pn){
+            break;
+        }
+        while(p1!=pn&&nodes[p1].k==i){
+            auto &now = nodes[p1++];
+            ans[now.q]=xdir[now.x];
+        }
+    }
+    for(int i=1;i<=q;i++){
+        cout<<ans[i]<<endl;
+    }
+}
+
+int readint(){
+    int x=0,w=1;
+    char ch=0;
+    while(!isdigit(ch)){
+        if(ch=='-')w=-1;
+        ch=getchar();
+    }
+    while(isdigit(ch)){
+        x=x*10+(ch-'0');
+        ch=getchar();
+    }
+    return x*w;
+}
\ No newline at end of file
diff --git a/xmake.lua b/xmake.lua
index 9652163..cf58a5c 100644
--- a/xmake.lua
+++ b/xmake.lua
@@ -104,4 +104,12 @@ target("U88589")
     for v=1,2 do 
         local s=tostring(v)
         add_tests(s,{files="./day10/U88589/*.cpp",runargs={s..".in",s..".ans"},defines="OITEST",run_timeout=1000})
+    end 
+
+target("U178578")
+    set_rundir("./day10/U178578")
+    add_files("./day10/U178578/*.cpp")
+    for v=1,3 do 
+        local s=tostring(v)
+        add_tests(s,{files="./day10/U178578/*.cpp",runargs={"bubble"..s..".in","bubble"..s..".ans"},run_timeout=1000,defines="OITEST"})
     end 
\ No newline at end of file