Add values to a map,delete values from a map by using list?

List<Account> ls = [select Id,Name from Account];
Map<Id, Account> m = new Map<Id, Account>(ls);

PutAll

Map<String, String> map1 = new Map<String, String>();
map1.put('Red','FF0000');
Map<String, String> map2 = new Map<String, String>();
map2.put('Blue','0000FF');
// Add map1 entries to map2
map2.putAll(map1);
System.assertEquals(2, map2.size());

List<Account> accts = new List<Account>();
accts.add(new Account(Name='Account1'));
accts.add(new Account(Name='Account2'));
// Insert accounts so their IDs are populated.
insert accts;
Map<Id, Account> m = new Map<Id, Account>();
// Add all the records to the map.
m.putAll(accts);
System.assertEquals(2, m.size());

REmove :-

Map<String, String> colorCodes = new Map<String, String>();
colorCodes.put('Red', 'FF0000');
colorCodes.put('Blue', '0000A0');
String myColor = colorCodes.remove('Blue');
String code2 = colorCodes.get('Blue');
System.assertEquals(null, code2);

REmove list

Map<String, String> colorCodes = new Map<String, String>();
colorCodes.put('Red', 'FF0000');
colorCodes.put('Blue', '0000A0');
List<String> colorCodeList = new List<String>();
colorCodeList.add('Blue');
for(String str: colorCodeList) 
{
      colorCodes.remove(str);
}

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