private void dataGridView1_MouseClick(object sender, MouseEventArgs e)
        {
            int N = Convert.ToInt32(textBox1.Text);
            dataGridView1.RowCount = N;
            dataGridView1.ColumnCount = 1;
            dataGridView1.AllowUserToAddRows = false;
            dataGridView1.ColumnHeadersVisible = false;
            dataGridView1.RowHeadersVisible = false;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int N = Convert.ToInt32(textBox1.Text);
            int[] niz = new int[N];
            int maks = 0;
            for (int i = 0; i < N; i++)
            {
                niz[i] = Convert.ToInt32(dataGridView1[0, 1].Value);
                if(niz[i] > maks)
                    maks = niz[i];
            }
            textBox2.Text = maks.ToString();
        }