diff --git a/mainEx4.cpp b/mainEx4.cpp
deleted file mode 100644
index 2d9a96a..0000000
--- a/mainEx4.cpp
+++ /dev/null
@@ -1,57 +0,0 @@
-#include <iostream>
-#include <cmath>  
-#include <cassert>  
-#include <vector>
-#include <iomanip>
-using namespace std;
-
-double NormalSeries(size_t N)
-{
-    double sum = 0.0;
-    for (size_t i = 1; i <= N; ++i)
-    {
-        sum += 1.0 / (double(i) * double(i));
-    }
-    return sum;
-}
-
-
-double KahanSeries(size_t N)
-{
-    double sum = 0.0;
-    double c = 0.0; 
-    for (size_t i = 1; i <= N; ++i) {
-        double term = 1.0 / (double(i) * double(i));
-        double y = term - c;
-        double t = sum + y;
-        c = (t - sum) - y;
-        sum = t;
-    }
-    return sum;
-}
-
-int main()
-{
-    const double pi2_over_6 = (M_PI * M_PI) / 6.0;
-    // vector<size_t> ns = {10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000};
-    vector<size_t> ns = {1000000, 10000000, 100000000, 500000000, 1000000000};
-
-
-    for (size_t n : ns)
-    {
-        double s_norm  = NormalSeries(n);
-        double s_kahan = KahanSeries(n);
-        double err_norm = fabs(s_norm - pi2_over_6);
-        double err_kahan = fabs(s_kahan - pi2_over_6);
-        
-        cout.setf(ios::fixed);
-        cout.precision(10);
-        cout << "\n--- n = " << n << " ---" << endl;
-        cout << "Normal summation: " << s_norm << endl;
-        cout << "Normal error: " << err_norm << endl;
-        cout << "Kahan summation:  " << s_kahan  << endl;
-        cout << "Kahan error:  " << err_kahan  << endl;
-    }
-
-    return 0;
-}