#include <vector>
#include <initializer_list>
#include <algorithm>
#include <random>
#include <iostream>
#include <ctime>
#include "List.h"

using namespace std;
using namespace List_h;

void foo() {
    Skip_list ll;

    for (auto i = -50; i < 50000; ++i) {
        ll.push_back(i);
    }

    ll.display();
}

int main() {
    constexpr int border = 8000000;
    Skip_list sl;
    Slink_list sll;    

    for (auto i = 0; i < border; ++i) {
        sl.push_back(i);
        sll.push_back(i);
    }

    int val;

    std::cout << "Please enter a number to search: ";
    while (std::cin >> val) {

        clock_t t;

        t = clock();

        /*if (sl.search(val)) {
            std::cout << val << " was found" << std::endl;
        }
        else {
            std::cout << val << " was not found" << std::endl;
        }*/

        bool vt = sl.search(val);

        t = clock() - t;

        std::cout << "Search in the skip list took me " << t << " cycles (" << static_cast<float> (t) / CLOCKS_PER_SEC << " seconds).\n";

        t = clock();

        const Link *p = sll.find(val);

        t = clock() - t;

        std::cout << "Search in the singly linked list took me " << t << " cycles (" << static_cast<float> (t) / CLOCKS_PER_SEC << " seconds).\n";

        if (vt) {
            std::cout << "Value " << p->val << " was found\n";
        }
    }

    return 0;
}
#include <iostream>
#include "List.h"

using namespace std;
using namespace List_h;

void foo() {
    Skip_list ll;

    for (auto i = -50; i < 50000; ++i) {
        ll.push_back(i);
    }

    ll.display();
}

int main() {
    Skip_list sl;
    
    sl.push_back(3);
    sl.push_back(6);
    sl.push_back(7);
    sl.push_back(9);
    sl.push_back(12);
    sl.push_back(17);
    sl.push_back(19);
    sl.push_back(25);
    sl.push_back(26);

    sl.insert(40, 40);
    sl.push_front(1);

    sl.delete_node(1);
    sl.delete_node(17);

    sl.display();

    int val;

    std::cout << "Please enter a number to search: ";
    std::cin >> val;

    if (sl.search(val)) {
        std::cout << val << " was found" << std::endl;
    }
    else {
        std::cout << val << " was not found" << std::endl;
    }

    return 0;
}
--- 
+++ 
@@ -1,4 +1,9 @@
+#include <vector>
+#include <initializer_list>
+#include <algorithm>
+#include <random>
 #include <iostream>
+#include <ctime>
 #include "List.h"
 
 using namespace std;
@@ -15,36 +20,48 @@
 }
 
 int main() {
+    constexpr int border = 8000000;
     Skip_list sl;
-    
-    sl.push_back(3);
-    sl.push_back(6);
-    sl.push_back(7);
-    sl.push_back(9);
-    sl.push_back(12);
-    sl.push_back(17);
-    sl.push_back(19);
-    sl.push_back(25);
-    sl.push_back(26);
+    Slink_list sll;    
 
-    sl.insert(40, 40);
-    sl.push_front(1);
-
-    sl.delete_node(1);
-    sl.delete_node(17);
-
-    sl.display();
+    for (auto i = 0; i < border; ++i) {
+        sl.push_back(i);
+        sll.push_back(i);
+    }
 
     int val;
 
     std::cout << "Please enter a number to search: ";
-    std::cin >> val;
+    while (std::cin >> val) {
 
-    if (sl.search(val)) {
-        std::cout << val << " was found" << std::endl;
-    }
-    else {
-        std::cout << val << " was not found" << std::endl;
+        clock_t t;
+
+        t = clock();
+
+        /*if (sl.search(val)) {
+            std::cout << val << " was found" << std::endl;
+        }
+        else {
+            std::cout << val << " was not found" << std::endl;
+        }*/
+
+        bool vt = sl.search(val);
+
+        t = clock() - t;
+
+        std::cout << "Search in the skip list took me " << t << " cycles (" << static_cast<float> (t) / CLOCKS_PER_SEC << " seconds).\n";
+
+        t = clock();
+
+        const Link *p = sll.find(val);
+
+        t = clock() - t;
+
+        std::cout << "Search in the singly linked list took me " << t << " cycles (" << static_cast<float> (t) / CLOCKS_PER_SEC << " seconds).\n";
+
+        if (vt) {
+            std::cout << "Value " << p->val << " was found\n";
+        }
     }
 
     return 0;
Change example a little bit
