Is it be possible to write it more cleaner way using linq.

```
//retrieved from db
List<User> existingList = new List<User>()
{
new User() {
Id = 1,
Name = "test1",
City = "City1"
},
new User() {
Id = 2,
Name = "test2",
City = "City"
}
};

//modified by ui
List<User> modifiedlist = new List<User>()
{
new User() {
Id = 1,
Name = "test1",
City = "City1"
},
new User() {
Id = 3,
Name = "test3",
City = "City3"
}
};

```

\*\*in db: (Going By modified list) I need to add user 3 and remove user 2 and don't bother about 1. 

\*\*for deleting user2, I am looping through existing list and if not present in modified list, then remove 2. \*\*for adding user3, i am looping through modified list and if not present in existing list, add 3