1 00:00:13,900 --> 00:00:18,760 Hello and welcome to the golden programming language course in this session. 2 00:00:18,790 --> 00:00:21,010 We want to talk about Maps concept. 3 00:00:25,580 --> 00:00:27,050 Maps and go blank. 4 00:00:29,140 --> 00:00:37,360 And that is a data structure that provides you with an on older collection of key value pairs, mats 5 00:00:37,360 --> 00:00:44,770 are also sometimes called associated arrays in the hash tables in Java or dictionaries in Python. 6 00:00:45,520 --> 00:00:54,100 Maps are used to look up the value byte is associated key U.S. values into the map based on a key. 7 00:00:55,000 --> 00:01:01,030 This rings of a map is its ability to retrieve data quickly based on the key. 8 00:01:01,540 --> 00:01:07,120 It key warps like an index pointing to the value you associate with that key. 9 00:01:08,360 --> 00:01:15,640 And that is implemented using a hash title, which is providing fast and loose run on the data element, 10 00:01:15,640 --> 00:01:19,420 and you can easily retrieve a value by providing the key. 11 00:01:20,110 --> 00:01:27,430 Maps are on ordered collections, and there is no way to predict the order in which the key value pairs 12 00:01:27,430 --> 00:01:28,420 will be returned. 13 00:01:28,810 --> 00:01:32,320 Every iteration over a map could return in a different order. 14 00:01:32,950 --> 00:01:35,650 You can see maps in the following table. 15 00:01:38,000 --> 00:01:45,950 She has to be distinct in the map value chain IQ industry case, you can access the key value pair of 16 00:01:45,950 --> 00:01:51,260 a map using key key in a map acts like an index in an array. 17 00:01:56,240 --> 00:01:58,100 Maps specification. 18 00:02:00,000 --> 00:02:04,230 Go land mass is a collection of old dictators of key value. 19 00:02:04,470 --> 00:02:11,790 It's widely used because it provides new crops and values that can retreat, update or delete with the 20 00:02:11,790 --> 00:02:12,710 help of peace. 21 00:02:14,710 --> 00:02:19,810 It is a reference to a hash table due to its reference time. 22 00:02:20,080 --> 00:02:24,910 It is inexpensive to pass, for example, for a 64 bit machine. 23 00:02:25,150 --> 00:02:28,250 It takes eight points and 42 Big Machine. 24 00:02:28,300 --> 00:02:30,730 It takes four bites in maths. 25 00:02:30,730 --> 00:02:40,090 The values are not unique like keys and can be of any type like in float 64 room S2 point to a reference 26 00:02:40,090 --> 00:02:42,010 type, map type and etc.. 27 00:02:43,630 --> 00:02:47,920 In maps, you can only add value when the map is initialized. 28 00:02:47,950 --> 00:02:53,080 If you try to add value in the uncivilised map, then the compiler will through any rule. 29 00:02:56,590 --> 00:02:58,810 These are the Maps specification. 30 00:03:01,420 --> 00:03:08,350 In the maps, a key must be unique and always in the type which is compatible using equal to operate 31 00:03:08,350 --> 00:03:12,310 or or the Typekit support, not equal to operator. 32 00:03:12,700 --> 00:03:21,520 So most of the built in time can be used as a key like an envelope, 64 room sitting comparable area 33 00:03:21,520 --> 00:03:29,410 in structure pointer and said throw the data types luck slice and non-credible arrays and instruments 34 00:03:29,410 --> 00:03:32,440 or custom data times which are not comparable. 35 00:03:32,590 --> 00:03:34,510 Don't use as a map key. 36 00:03:37,280 --> 00:03:44,000 The type of keys and type of values must be of the same time, different types of keys and values in 37 00:03:44,000 --> 00:03:45,950 the same maps are not alone. 38 00:03:46,280 --> 00:03:49,280 But the type of key and the type values can differ. 39 00:03:50,220 --> 00:03:57,840 And the map is also known as a hash map hash stated unaltered map dictionary or associated array. 40 00:03:58,770 --> 00:03:59,160 OK. 41 00:03:59,520 --> 00:04:05,220 In order not to prolong the time of decision, we've been finished and we will continue the content 42 00:04:05,220 --> 00:04:06,270 in the next session. 43 00:04:06,570 --> 00:04:07,170 Goodbye.