diff --git a/src/CSP-S2023/CSP-S.pdf b/src/CSP-S2023/CSP-S.pdf
new file mode 100644
index 0000000..6162316
Binary files /dev/null and b/src/CSP-S2023/CSP-S.pdf differ
diff --git a/src/CSP-S2023/lock/lock.cpp b/src/CSP-S2023/lock/lock.cpp
new file mode 100644
index 0000000..4c101f4
--- /dev/null
+++ b/src/CSP-S2023/lock/lock.cpp
@@ -0,0 +1,115 @@
+#include <algorithm>
+#include <array>
+#include <cstring>
+#include <iostream>
+#include <istream>
+#include <iterator>
+#include <ostream>
+#include <set>
+#include <utility>
+
+using ll = long long;
+using ull = unsigned long long;
+const ll max_num = 6;
+short n, arr[max_num];
+std::set<std::array<short, max_num>> ans_set;
+
+template<class T,size_t S>
+std::ostream &operator<<(std::ostream &os, const std::array<T,S> &s){
+    os<<"array [ ";
+    if(!s.empty()){
+        auto now_it = s.begin();
+        const auto rbegin = s.rbegin();
+        while(*now_it!=*rbegin){
+            os<<*now_it<<", ";
+            ++now_it;
+        }
+        os<<*rbegin<<" ]";
+    }else{
+        os<<"}";
+    }
+    return os;
+}
+
+template<class T>
+std::ostream &operator<<(std::ostream &os, const std::set<T> &s){
+    os<<"set { ";
+    if(!s.empty()){
+        auto now_it = s.begin();
+        const auto rbegin = s.rbegin();
+        while(*now_it!=*rbegin){
+            os<<*now_it<<", ";
+            ++now_it;
+        }
+        os<<*rbegin<<" }";
+    }else{
+        os<<"}";
+    }
+    return os;
+}
+
+#ifdef ONLINE_JUDGE
+#define DEBUG(code)
+#else
+#define DEBUG(code)code
+#endif
+
+ll arr_to_ll(const ll *const arr){
+    ll ret{};
+    for(ll i{1};i<=5;i++){
+        DEBUG(std::cout<<ret<<'\n';)
+        ret=ret*10 + (arr[i]==0?-1:arr[i]);
+    }
+    DEBUG(std::cout<<ret<<'\n';)
+    return ret;
+}
+
+int main(){
+    std::iostream::sync_with_stdio(false), std::cin.tie(nullptr), std::cout.tie(nullptr);
+    std::cin>>n;
+    for(ll i{1};i<=n;i++){
+        for(ll j{1};j<=5;j++){
+            std::cin>>arr[j];
+        }
+        std::set<std::array<short, max_num>> tmp_set;
+        for(ll j{1};j<=5;j++){
+            for(ll k{1};k<=9;k++){
+                std::array<short, max_num> new_arr{};
+                memcpy(new_arr.begin(), arr, sizeof(arr));
+                new_arr[j]  = (new_arr[j] + k) % 10;
+                DEBUG(
+                    for(ll i{1};i<=5;i++){
+                        std::cout<<new_arr[i]<<' ';
+                    }
+                    std::cout<<'\n';
+                )
+                tmp_set.insert(new_arr);
+            }
+        }
+        for(ll j{1};j<=4;j++){
+            for(ll k{1};k<=9;k++){
+                std::array<short, max_num> new_arr{};
+                memcpy(new_arr.begin(), arr, sizeof(arr));
+                new_arr[j]  = (new_arr[j] + k) % 10;
+                new_arr[j+1]  = (new_arr[j+1] + k) % 10;
+                DEBUG(
+                    for(ll i{1};i<=5;i++){
+                        std::cout<<new_arr[i]<<' ';
+                    }
+                    std::cout<<'\n';
+                )
+                tmp_set.insert(new_arr);
+            }
+        }
+        DEBUG(std::cout<<tmp_set<<'\n';)
+        std::set<std::array<short, max_num>> new_ans_set;
+        if(i!=1){
+            std::set_intersection(ans_set.begin(), ans_set.end(), tmp_set.begin(), tmp_set.end(), std::inserter(new_ans_set, new_ans_set.end()));
+        }else{
+            new_ans_set = std::move(tmp_set);
+        }
+        ans_set = std::move(new_ans_set);
+        DEBUG(std::cout<<ans_set<<'\n';)
+    }
+    std::cout<<ans_set.size()<<'\n';
+}
\ No newline at end of file
diff --git a/src/P7913/P7913.cpp b/src/P7913/P7913.cpp
index f14bfc3..aeb09bc 100644
--- a/src/P7913/P7913.cpp
+++ b/src/P7913/P7913.cpp
@@ -13,8 +13,11 @@ void print(const Args&...args){
 
 const ll max_m = 1e5;
 ll n, m1, m2, arr1[max_m], arr2[max_m];
+/*
 
 
+*/
+
 int main(){
     read(n,m1,m2);
     for(ll i{1};i<=m1;i++){