diff --git a/Makefile b/Makefile
index 8058fac..e450f6f 100755
--- a/Makefile
+++ b/Makefile
@@ -1,22 +1,34 @@
+	export BUILD_CMD=clang++ -Wall -std=c++17 -Wall -Wextra
+
 setup:
 	mkdir build
 
 sheet0:
-	g++ src/sheet0.cpp -o ./build/sheet0
+	${BUILD_CMD} src/sheet00.cpp -o build/sheet0
 	chmod +x build/sheet0
 	build/sheet0
 
 sheet01:
-	g++ src/sheet01.cpp -o ./build/sheet01
+	${BUILD_CMD} src/sheet01.cpp -o build/sheet01
 	chmod +x build/sheet01
 	build/sheet01
 
 sheet02:
-	g++ src/sheet02.cpp -o ./build/sheet02
+	${BUILD_CMD} src/sheet02.cpp -o build/sheet02
 	chmod +x build/sheet02
 	build/sheet02
 
+sheet03:
+	${BUILD_CMD} src/sheet03.cpp src/MyType.cpp -o build/sheet03
+	chmod +x build/sheet03
+	build/sheet03
+
+sheet04:
+	${BUILD_CMD} src/sheet04.cpp -o build/sheet04
+	chmod +x build/sheet04
+	build/sheet04
+
 pizza:
-	g++ src/pizza.cpp -o ./build/pizza
+	${BUILD_CMD} src/pizza.cpp -o build/pizza
 	chmod +x build/pizza
 	build/pizza
diff --git a/headers/MyType.h b/headers/MyType.h
new file mode 100644
index 0000000..d33ee14
--- /dev/null
+++ b/headers/MyType.h
@@ -0,0 +1,15 @@
+#ifndef MYTYPE_H
+#define MYTYPE_H
+#include <string>
+struct MyType{
+    std::string name;
+    unsigned age;
+
+    MyType(std::string n, unsigned a);
+    ~MyType();
+    MyType(const MyType &t);
+    MyType& operator= (const MyType &t);
+    MyType(MyType &&t);
+    MyType& operator= (MyType &&t);
+};
+#endif
\ No newline at end of file
diff --git a/src/MyType.cpp b/src/MyType.cpp
new file mode 100644
index 0000000..3fa9b66
--- /dev/null
+++ b/src/MyType.cpp
@@ -0,0 +1,9 @@
+#include "../headers/MyType.h"
+#include <string>
+#include <iostream>
+    MyType::MyType(std::string n, unsigned a) : name(n), age(a) {std::cout << "ctor\n";}
+    MyType::~MyType() {std::cout << "dtor \n";}
+    MyType::MyType(const MyType &t) { std::cout << "copy ctor\n";}
+    MyType& MyType::operator= (const MyType &t) { std::cout << "copy ass ctor\n"; return *this;}
+    MyType::MyType(MyType &&t){std::cout << "move ctor\n";}
+    MyType& MyType::operator= (MyType &&t) { std::cout << "move ass ctor\n"; return t;}
\ No newline at end of file
diff --git a/src/sheet03.cpp b/src/sheet03.cpp
new file mode 100644
index 0000000..818e2c5
--- /dev/null
+++ b/src/sheet03.cpp
@@ -0,0 +1,123 @@
+#include <string>
+#include <iostream>
+#include <cmath>
+#include <vector>
+#include "../headers/MyType.h"
+
+double calculate(int argc, char **argv);
+void pol2cart(double r, double phi, double &x, double &y);
+void pascal(int argc, char **argv);
+void pascal_mem(int argc, char **argv);
+
+int main(int argc, char **argv)
+{
+    MyType j("jj", 69);
+    MyType cj(j);
+    MyType caj("jj",420);
+    caj = j;
+    MyType mj(std::move(j));
+    MyType maj("jj", 69);
+    maj = std::move(cj);
+    std::cout << calculate(argc, argv) << '\n';
+    double x = 0;
+    double y = 0;
+    pol2cart(0.5, 0, x, y);
+    std::cout << x << " " << y << '\n';
+    pascal(argc, argv);
+    std::cout << '\n';
+    pascal_mem(argc, argv);
+    return 0;
+}
+
+double calculate(int argc, char **argv)
+{
+    if(argc != 4)
+    {
+        return std::nan("");
+    }
+
+    switch(argv[2][0])
+    {
+        case '+':
+            return std::stod(argv[1]) + std::stod(argv[3]);
+        case '-':
+            return std::stod(argv[1]) - std::stod(argv[3]);
+        case 'x':
+            return std::stod(argv[1]) * std::stod(argv[3]);
+        case '/':
+            return std::stod(argv[1]) / std::stod(argv[3]);
+        default:
+            std::cout << "Invalid operand: " << argv[2][0] << '\n';
+            return std::nan("");
+    }
+}
+
+void pol2cart(double r, double phi, double &x, double &y)
+{
+    x = r * cos(phi);
+    y = r * sin(phi);
+}
+
+void pascal(int argc, char **argv)
+{
+    if (argc != 2 || std::stol(argv[1]) == 0) { return; }
+
+    unsigned depth = std::stol(argv[1]);
+
+    std::vector<std::vector<unsigned long long>> pascal(depth+1, std::vector<unsigned long long>(depth+1,0));
+    pascal[1][1] = 1;
+    for(unsigned long long y=2; y<depth; ++y)
+    {
+        for(unsigned long long x=2; x<=depth; ++x)
+        {
+            pascal[y][x] = pascal[y-1][x-1] + pascal[y-1][x];
+            if(pascal[y][x]!=0)
+            {
+                std::cout << pascal[y][x] << '\t';
+            }
+        }
+        std::cout<< '\n';
+    }
+}
+
+void pascal_mem(int argc, char **argv)
+{
+    if (argc != 2 ) { return; }
+
+    unsigned depth = std::stol(argv[1]);
+
+    if(depth == 1 )
+    {
+        std::cout << "1\n";
+    }
+    else if(depth==0)
+    {
+        return;
+    }
+
+    unsigned vector_depth = (depth*depth-depth)/2;
+    std::vector<unsigned long long> pascal(vector_depth,0);
+    pascal[0] = 1;
+    std::cout << "1\n";
+    // pascal[1] = 1;
+    // pascal[2] = 1;
+    // std::cout << "1\t1\n";
+    unsigned rel_index = 2;
+    while(rel_index<=depth)
+    {
+        unsigned index = (rel_index*rel_index-rel_index)/2;
+        unsigned prev_index = ((rel_index-1)*(rel_index-1)-(rel_index-1))/2;
+        unsigned next_index = ((rel_index+1)*(rel_index+1)-(rel_index+1))/2;
+
+        pascal[index] = 1; 
+        std::cout << pascal[index] << '\t';
+        for(unsigned i=prev_index; i<index-1; ++i)
+        {
+            pascal[i+rel_index] = pascal[i] + pascal[i+1];
+            std::cout << pascal[i+rel_index] << '\t';
+        }
+        pascal[next_index-1] = 1;
+        std::cout << pascal[next_index-1] << '\n';
+        ++rel_index;
+    }
+}
\ No newline at end of file
diff --git a/src/sheet04.cpp b/src/sheet04.cpp
new file mode 100644
index 0000000..65a1e9f
--- /dev/null
+++ b/src/sheet04.cpp
@@ -0,0 +1,77 @@
+#include <cstddef>
+#include <array>
+#include <initializer_list>
+#include <cmath>
+class vec
+{
+    private:
+    const double nan = std::nan("");
+    unsigned vec_size;
+    double *vector;
+    public:
+    vec(size_t size) : vec_size(size), vector(new double[size]) {}
+    vec(size_t size, double ival) : vec_size(size), vector(new double[size])
+    {
+        for(size_t i=0; i<size;++i) { vector[i]=ival; }
+    }
+
+    vec(std::initializer_list<double> ilist) : vec_size(ilist.size()), vector(new double[vec_size]) {
+        size_t i = 0;
+        for(std::initializer_list<double>::iterator itr = ilist.begin(); itr!=ilist.end();++itr)
+        {
+            vector[i++] = *itr;
+        }
+    }
+
+    ~vec() {delete[] vector;}
+    vec(const vec &m) : vec_size(m.vec_size), vector(new double[vec_size])
+    {
+        for(size_t i=0; i<vec_size;++i)
+        {
+            vector[i] = m.vector[i];
+        }
+    }
+
+    vec& operator= (const vec &m)
+    {
+        if(this!=&m)
+        {
+            vec_size = m.vec_size;
+            delete[] vector;
+            vector = new double[vec_size];
+
+            for(size_t i = 0; i<vec_size; ++i)
+            {
+                vector[i] = m.vector[i];
+            }
+        }
+        return *this;
+    }
+
+    vec(vec &&m) : vec_size(m.vec_size), vector(new double[vec_size])
+    {
+        vector = std::move(m.vector);
+    }
+
+    vec& operator= (vec &&m)
+    {
+        vec_size = m.vec_size;
+        vector = std::move(m.vector);
+        return *this;
+    }
+
+    size_t size()
+    {
+        return vec_size;
+    }
+
+    double& operator[] (size_t idx)
+    {
+        if(idx>vec_size)
+        {
+            return nan;
+        }
+
+        return vector[idx];
+    }
+};
\ No newline at end of file