diff --git a/Makefile b/Makefile
index 65f48bc..e450f6f 100644
--- a/Makefile
+++ b/Makefile
@@ -23,6 +23,11 @@ sheet03:
 	chmod +x build/sheet03
 	build/sheet03
 
+sheet04:
+	${BUILD_CMD} src/sheet04.cpp -o build/sheet04
+	chmod +x build/sheet04
+	build/sheet04
+
 pizza:
 	${BUILD_CMD} src/pizza.cpp -o build/pizza
 	chmod +x build/pizza
diff --git a/src/sheet03.cpp b/src/sheet03.cpp
index 7402b1a..818e2c5 100644
--- a/src/sheet03.cpp
+++ b/src/sheet03.cpp
@@ -24,6 +24,8 @@ int main(int argc, char **argv)
     pol2cart(0.5, 0, x, y);
     std::cout << x << " " << y << '\n';
     pascal(argc, argv);
+    std::cout << '\n';
+    pascal_mem(argc, argv);
     return 0;
 }
 
@@ -77,39 +79,45 @@ void pascal(int argc, char **argv)
         std::cout<< '\n';
     }
 }
-unsigned fibonacci_nonrec(unsigned n)
-{
-    unsigned fibo = 0;
-    unsigned prev_fibo = 1;
-    unsigned prev_prev_fibo = 0;
 
-   for(int i=2; i<=n; ++i)
-    {
-        fibo = prev_fibo + prev_prev_fibo;
-        prev_prev_fibo = prev_fibo;
-        prev_fibo = fibo;
-    }
-
-    return fibo;
-}
 void pascal_mem(int argc, char **argv)
 {
-    
-    if (argc != 2 || std::stol(argv[1]) == 0) { return; }
+    if (argc != 2 ) { return; }
 
     unsigned depth = std::stol(argv[1]);
-    depth = (depth*depth-depth)/2;
-    std::vector<unsigned long long> pascal(depth,0);
-    pascal[0] = 1;
-    for(unsigned long long i=1; i<depth; i=(i*i-i)/2)
+
+    if(depth == 1 )
     {
-        for(unsigned long long j=1; j<=i;++j)
-        {
-
-        }
-        pascal[i] = pascal[i-1];
-        ++i;
+        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..e099105
--- /dev/null
+++ b/src/sheet04.cpp
@@ -0,0 +1,32 @@
+#include <cstddef>
+#include <array>
+#include <initializer_list>
+class vec
+{
+    private:
+    unsigned size;
+    double *vector;
+    public:
+    vec(size_t size) : size(size), vector(new double[size]) {}
+    vec(size_t size, double ival) : size(size), vector(new double[size])
+    {
+        for(size_t i=0; i<size;++i) { vector[i]=ival; }
+    }
+
+    vec(std::initializer_list<double> ilist) : size(ilist.size()), vector(new double[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) : vector(new double[m.size])
+    {
+        for(size_t i=0; i<m.size;++i)
+        {
+            vector[i] = m.vector[i];
+        }
+    }
+};
\ No newline at end of file