private void Difference_Click(object sender,EventArgs e)
{
if(this.setOne != null && this.setTwo != null){
Result.Clear();
result.clear();
result = setOne.diff(setTwo);
string[] arr = null;
arr = result.getAll(arr);
size = result.size();
for(int i = 0;i<size;i++) {
if(arr[i] != null) {
Result.Items.Add(arr[i]);
}
}
}
}