diff --git a/lectures/optimization/erase/map_erase_fast.cpp b/lectures/optimization/erase/map_erase_fast.cpp
deleted file mode 100644
index ccbd380..0000000
--- a/lectures/optimization/erase/map_erase_fast.cpp
+++ /dev/null
@@ -1,20 +0,0 @@
-#include <iostream>
-#include <map>
-
-int main() {
-    const int N = 1000000;
-    std::map<int, int> m;
-
-    // fill the map with some values
-    for (int i = 0; i < N; ++i) {
-        m[i] = i;
-    }
-
-    // erase all elements using iterators
-    for (std::map<int, int>::iterator itr = m.begin(); itr != m.end(); ) {
-        itr = m.erase(itr); // erase using iterator and move to the next element
-    }
-
-    return 0;
-}
-
diff --git a/lectures/optimization/erase/map_erase_slow.cpp b/lectures/optimization/erase/map_erase_slow.cpp
deleted file mode 100644
index 5b46dd2..0000000
--- a/lectures/optimization/erase/map_erase_slow.cpp
+++ /dev/null
@@ -1,20 +0,0 @@
-#include <iostream>
-#include <map>
-
-int main() {
-    const int N = 1000000;
-    std::map<int, int> m;
-
-    // fill the map with some values
-    for (int i = 0; i < N; ++i) {
-        m[i] = i;
-    }
-
-    // erase by key
-    for (int i = 0; i < N; ++i) {
-        m.erase(i);
-    }
-
-    return 0;
-}
-