diff --git a/a.cpp b/a.cpp
index 39164866..875b0b57 100644
--- a/a.cpp
+++ b/a.cpp
@@ -3,19 +3,50 @@
 
 using namespace std;
 
-int main(){
-	vector<int> arr{-1, 3, -3, 4,5};
-  	vector<int> temp(arr.size()+1,0);
-	for(int i=0;i<arr.size();i++){
-    	if(arr[i]<arr.size()+1 && arr[i]>0){
-          temp[arr[i]]=1;
+int compress(vector<char>& chars) {
+    vector<char> vec;
+    vector<int> num;
+    char lc=chars[0];
+    int ln=1;
+    int j=0;
+    for(int i=1;i<chars.size();i++){
+        if(chars[i]==lc){
+            ln++;
+        }
+        else{
+            vec[j]=lc;
+            num[j]=ln;
+            j++;
+            lc=chars[i];
+            ln=1;
         }
     }
-    int i;
-  	for(i=1;i<temp.size();i++){
-      if(temp[i]==0)break;
+    vec[j]=lc;
+    num[j]=ln;
+    vector<char> &res=chars;
+    res.clear();
+    for(int i=0;i<vec.size();i++){
+        res.push_back(vec[i]);
+        if(num[i]==1)continue;
+        if(num[i]>0){
+            char temp = char(num[i]%10-0+'0');
+            res.push_back(temp);
+            num[i]/=10;
+        }
     }
-    cout<<i<<endl;
+    return res.size();
+}
 
-	return 0;
+int main(){
+    vector<char> chars={'a','a','b'};
+    for(auto a:chars){
+        cout<<a<<endl;
+    }
+    compress(chars);
+
+    for(auto a:chars){
+        cout<<a;
+    }
+    cout<<endl;
+    return 0;
 }
\ No newline at end of file