diff --git a/lab18/t1.cpp b/lab18/t1.cpp
new file mode 100644
index 0000000..a467f39
--- /dev/null
+++ b/lab18/t1.cpp
@@ -0,0 +1,20 @@
+#include <iostream>
+
+int main() {
+    unsigned n;
+    std::cin >> n;
+    unsigned i = 0, i_min = 0;
+    double t0 = 0., t_min = 1e9;
+    for (unsigned i = 0; i < n; i++) {
+        double t;
+        std::cin >> t;
+        t0 += t;
+        if (t_min > t0) {
+            t_min = 0;
+            i_min = i;
+        }
+        std::cout << t0 << ' ';
+        t0 -= 1.;
+    }
+    std::cout << std::endl << i_min + 1;
+}
\ No newline at end of file
diff --git a/lab18/t15.cpp b/lab18/t15.cpp
new file mode 100644
index 0000000..38cb55e
--- /dev/null
+++ b/lab18/t15.cpp
@@ -0,0 +1,35 @@
+#include <iostream>
+#include <vector>
+#include <algorithm>
+
+int main() {
+    std::cout << "Введіть масив цілих чисел через пробіл: ";
+    std::vector<int> numbers;
+    int num;
+    while (std::cin >> num) {
+        numbers.push_back(num);
+    }
+
+    std::vector<int> L = numbers;
+    std::cout << "Елементи списку L у вихідному порядку: ";
+    for (int element : L) {
+        std::cout << element << " ";
+    }
+    std::cout << std::endl;
+
+    std::cout << "Елементи списку L у оберненому порядку: ";
+    for (auto it = L.rbegin(); it != L.rend(); ++it) {
+        std::cout << *it << " ";
+    }
+    std::cout << std::endl;
+
+    std::sort(L.begin(), L.end());
+    std::reverse(L.begin(), L.end());
+    std::cout << "Елементи списку L відсортовані за зростанням, але виведені у порядку спадання: ";
+    for (int element : L) {
+        std::cout << element << " ";
+    }
+    std::cout << std::endl;
+
+    return 0;
+}
diff --git a/lab18/t2.cpp b/lab18/t2.cpp
new file mode 100644
index 0000000..41b003e
--- /dev/null
+++ b/lab18/t2.cpp
@@ -0,0 +1,27 @@
+#include <iostream>
+#include <vector>
+#include <cmath>
+
+int main() {
+    unsigned n, d;
+    std::cin >> n >> d;
+    //std::vector<double> v(d);
+    for (unsigned i = 0; i < n; i++) {
+        double l = 0, q;
+        //for (auto& q : v) {
+        //    std::cin >> q;
+        //    l += q * q;
+        //}
+        for (unsigned j = 0; j < d; j++) {
+            std::cin >> q;
+            l += q*q;
+        }
+        double norm = std::sqrt(l);
+        std::cout << norm << std::endl;
+        // normalize
+        //for (auto q : v) {
+        //    std::cout << q / len << ' ';
+        //}
+        //std::cout << std::endl;
+    }
+}
\ No newline at end of file
diff --git a/lab18/t3.cpp b/lab18/t3.cpp
new file mode 100644
index 0000000..248bb7a
--- /dev/null
+++ b/lab18/t3.cpp
@@ -0,0 +1,20 @@
+#include <list>
+
+template<typename T>
+class Poly {
+public:
+    Poly() noexcept = default;
+    Poly(Poly&&) noexcept = default;
+    Poly(const Poly&) = default;
+    Poly& operator=(Poly&&) noexcept = default;
+    Poly& operator=(const Poly&) = default;
+    ~Poly() = default;
+
+    // TODO input, constructor
+private:
+    std::list<std::pair<int, T>> powers;
+};
+
+int main() {
+    // TODO
+}
\ No newline at end of file
diff --git a/lab18/t4.cpp b/lab18/t4.cpp
new file mode 100644
index 0000000..e343cad
--- /dev/null
+++ b/lab18/t4.cpp
@@ -0,0 +1,27 @@
+#include <algorithm>
+#include <vector>
+#include <iostream>
+
+int main() {
+    unsigned n, m;
+    std::vector<std::vector<double>> mat;
+
+    for (size_t i = 0; i < n; i++) {
+        std::vector<double> row(m);
+        for (auto& v : row) {
+            std::cin >> v;
+        }
+        row.emplace_back(std::move(row));
+    }
+
+    std::sort(mat.begin(), mat.end(), [](const auto& a, const auto& b){
+        return std::max_element(a.begin(), a.end()) > std::max_element(b.begin(), b.end());
+    });
+
+    for (const auto& row : mat) {
+        for (const auto& v : row) {
+            std::cout << v << ' ';
+        }
+        std::cout << std::endl;
+    }
+}
\ No newline at end of file