WEBVTT 00:00.810 --> 00:06.120 As you learned earlier, there is an interesting a very interesting fact about arrays. 00:06.240 --> 00:11.060 So we can access the arrays element using a pointer. 00:11.070 --> 00:16.290 So as you may know, a pointer is a variable that holds the address. 00:16.980 --> 00:18.110 Instead of value. 00:18.120 --> 00:25.560 So and since we discussed earlier that each element in the array has its own address, we can access 00:25.560 --> 00:28.230 each race element using its address. 00:28.230 --> 00:35.520 So to use a pointer as an array, we need to initialize to it to hold an array as shown here. 00:35.520 --> 00:46.300 So let's we're going to change it our this, my array and we will write this my for example my oxalate 00:46.350 --> 00:47.460 array here. 00:49.300 --> 00:51.280 Or let's actually write it from zero. 00:51.760 --> 00:57.970 So, as you know, we previously we manipulated some of the things here we did. 00:58.800 --> 01:01.260 And actually let's clear the main method. 01:01.260 --> 01:02.220 So we want to use it. 01:02.430 --> 01:10.170 We will use it anywhere and we will also clear this that we changed it. 01:10.170 --> 01:14.100 So we changed index two and index three. 01:14.130 --> 01:23.100 So in place of the index ten and as you can see it here, so in place of the index three, we will write 01:23.100 --> 01:24.930 the 87 index. 01:24.930 --> 01:29.610 Two, we will write 8787. 01:31.230 --> 01:33.420 And 69. 01:33.600 --> 01:36.270 69. 01:38.430 --> 01:39.060 Here. 01:41.380 --> 01:45.370 So now we're going to create our array here. 01:45.370 --> 01:47.470 So let's actually comment this. 01:48.720 --> 01:52.380 Comments and we will create a new integer pointer array. 01:52.380 --> 01:54.240 So integer, Peter. 01:54.350 --> 01:56.850 Peter new integer. 01:57.240 --> 02:00.180 This is going to be five size of integer. 02:00.180 --> 02:02.690 So one, two, three, four, five. 02:02.700 --> 02:04.680 Size of five, not the index five. 02:04.680 --> 02:11.430 So if you have five, uh, size of array, then we have the from zero. 02:11.430 --> 02:16.170 This means our maximum index is four by default. 02:16.200 --> 02:23.710 So here now we're going to create this 25, 2148 02:24.340 --> 02:28.380 827 30 Uh, no. 02:28.380 --> 02:31.950 40 2148 827. 02:32.220 --> 02:34.950 The 69 and 35. 02:36.150 --> 02:39.110 So this is an initialization. 02:39.240 --> 02:49.080 We have a pointer named Peter that points to the first element of an array containing five elements 02:49.080 --> 02:49.650 here. 02:50.490 --> 02:51.480 So. 02:52.790 --> 02:56.930 However, the variable holds the first arrays element address at START. 02:56.930 --> 03:02.750 So to access the next address, we can increment Peter variables. 03:03.140 --> 03:03.500 So. 03:03.500 --> 03:14.870 Peter plus plus we can increment the Peter variable, um, so that it will point to the next element 03:14.870 --> 03:15.140 here. 03:15.140 --> 03:17.690 So it will point to next element. 03:17.720 --> 03:26.000 Actually, yeah, we can increment this and so it will point to the next element and next element here. 03:26.240 --> 03:30.830 So we can use the wildcard symbol before the pointer name. 03:30.830 --> 03:32.560 And as you can see here. 03:32.570 --> 03:33.710 So. 03:35.800 --> 03:37.810 Let's first actually create some. 03:40.400 --> 03:41.210 Here. 03:46.470 --> 03:51.450 Here we will create a print this variable C out. 03:52.370 --> 03:53.210 See out. 03:54.600 --> 03:57.840 PDR, PDR and inline. 03:58.140 --> 04:02.250 And thus we will print this without the disk. 04:02.940 --> 04:06.120 Without this, the wild card symbol. 04:06.120 --> 04:06.750 So. 04:06.780 --> 04:08.970 PDR and end line. 04:09.580 --> 04:10.720 End line here. 04:10.720 --> 04:16.800 So the former statement in this code will print out the value that pointer points to. 04:16.810 --> 04:18.680 So let's actually firstly compile it. 04:18.700 --> 04:22.630 CLS and G++. 04:22.660 --> 04:24.010 Main.cpp. 04:25.400 --> 04:31.850 Edit And as you can see here, this is our pointer and this is our first element, as you can see here. 04:31.850 --> 04:37.190 So as we said earlier, the first this. 04:38.560 --> 04:39.700 So let's here. 04:39.700 --> 04:50.500 So this symbol p t r points to our 21. 04:50.500 --> 04:54.730 So the first element so equals the first. 04:55.720 --> 04:56.410 Element. 05:01.650 --> 05:04.370 However, if we write it like that. 05:04.380 --> 05:06.000 The P here. 05:07.290 --> 05:08.130 Peter. 05:08.250 --> 05:15.660 The Peter is just shows the entire address the address of in our memory that. 05:17.310 --> 05:19.200 Our array lives on it. 05:19.200 --> 05:23.270 So in this case it's going to print the address. 05:23.280 --> 05:25.380 So at. 05:26.080 --> 05:26.830 Rest. 05:28.300 --> 05:29.890 Of array. 05:33.010 --> 05:38.800 So this prints out the address of arrays, the second code line. 05:38.800 --> 05:45.490 And here this prints the first element, which is 21. 05:47.320 --> 05:51.460 So here we can access the value of each element. 05:52.330 --> 05:55.150 And the address as well as its index. 05:55.150 --> 05:58.180 So let's actually create some another example. 05:59.880 --> 06:00.570 Here. 06:00.600 --> 06:01.670 Let's, uh. 06:01.710 --> 06:02.220 Here. 06:02.220 --> 06:03.330 Clear that. 06:06.760 --> 06:07.330 Here. 06:07.330 --> 06:08.320 Clear that. 06:09.190 --> 06:09.970 Clear that. 06:09.970 --> 06:10.660 Clear that. 06:10.660 --> 06:11.530 Clear that. 06:25.570 --> 06:29.530 Here now, we will create something like that. 06:29.530 --> 06:32.170 So now we're going to create. 06:33.240 --> 06:33.900 Uh, the. 06:35.590 --> 06:41.220 Some code that we can access the value of each element and the address as well as the index. 06:41.230 --> 06:42.880 So the key out. 06:42.910 --> 06:43.350 Oops. 06:44.910 --> 06:46.110 The sea out. 06:49.170 --> 06:52.500 See out the r e here. 06:52.530 --> 06:58.680 E in this case, for example, to let's take E as a two and we will end line here. 06:58.710 --> 07:03.330 End line and see out tr. 07:04.660 --> 07:07.500 Again, he is a to here for example just. 07:07.860 --> 07:11.850 He also can be three, 4 or 0. 07:11.850 --> 07:15.980 But in this case it's going to print the address of our array here. 07:15.990 --> 07:23.220 So now let's actually go to CMD compiler application and run it. 07:24.570 --> 07:25.260 Here. 07:25.680 --> 07:29.160 So as you can see here, this prints. 07:29.160 --> 07:36.540 So in this case, our E was the E was equal to two. 07:36.540 --> 07:38.880 So we've written the two. 07:40.230 --> 07:44.790 Between these braces in the two code code lines. 07:44.790 --> 07:45.480 So. 07:46.280 --> 07:47.800 This is our. 07:49.880 --> 07:57.290 P t r, and this is our regular p r, which showed us the same result. 07:57.290 --> 08:01.490 If we use if you use that the. 08:03.420 --> 08:04.350 Index. 08:05.220 --> 08:06.330 We specified index. 08:06.330 --> 08:10.110 It will get us an same result here. 08:10.440 --> 08:18.930 So in next lecture we will create some code that we will initialize pointer, initialize the array length 08:18.930 --> 08:26.700 and we will also display each element by incrementing the pointer and we will move forward the pointer 08:26.700 --> 08:27.660 five times. 08:27.660 --> 08:29.400 So I'm waiting you in the next lecture.