Following code can be used to check if two arrays contain any similar item or not:
string[] allLocations = { "New
York", "London", "Washington", "India",
"Pakistan"};
string[] mainUSlocations = { "Boston",
"Los Angels", "New York" };
if (allLocations.ToList().Any(al =>
mainUSlocations.Contains(al)))
{
//Yor logic goes here
}