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After the return trip.

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Uh, the parameters.

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The function name.

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And have been determined.

5
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You need to define the body of the parameter.

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So we're going to first, uh, make the return time, then our function name for some.

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My function, uh, the parameters for this function is going to go, for example, my integer.

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And this is the function.

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Uh, but here.

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00:00:31,170 --> 00:00:39,570
So the code for a function must appear between a pair of braces here, as you can see here.

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So if the function returns the value, then the function must have at least one line.

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The last line in the function with the return statement here.

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So this must return the appropriate type or type that can be implicitly converted to the return type

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of the function.

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So as mentioned before, if the function is declared as auto here, the compiler will deduce the return

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type.

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So in this case, the return statement must return the same type.

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Now, when a function is called the compiler checks all the overloads of the function to find one that

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matches the parameter in the calling code.

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So if there is a no exact match, then the standard and those are defined.

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Type conversions are performed, so the values provided by the calling code may be different type from

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parentheses here.

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So parameters.

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So by default, parameters are passed by value and the copy is made.

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So which means that the.

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Parameters are treated as local variables in the function like that here.

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So you can't use the my integer variable outside the function here though these are the just local variables

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that you can use these variables inside the function.

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So.

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Uh, the variety of the function can decide to pass parameter by reference either through the pointer

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or a C++ reference.

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So pass by reference means that the variable in the calling code can be altered by the function, but

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this can control the by making the parameters constant here.

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So in which case, the reason for passing my reference is to prevent the potentially costly copying

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being made.

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So the built in arrays are always passed as a pointer to the first item to the array.

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Here, the compiler will create the temporaries when needed.

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So for example, when a parameter here for example, it's called void, F the F when a parameter is

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a const reference and the calling code pass the pass as a literal.

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A temporary object is created here and it's only available to the function here.

41
00:03:05,200 --> 00:03:13,750
Let's go to the function float and here we're going to make the F here.

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F 1.0, for example, or double double d d equals.

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2.0.

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As you know, this is the plot number.

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00:03:29,980 --> 00:03:31,390
And here.

46
00:03:31,870 --> 00:03:33,970
And we're going to.

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Add the F pass the the variable, the double variable to the r f function here, which returns nothing.

48
00:03:45,500 --> 00:03:48,620
But we have a const parameter here.

49
00:03:49,350 --> 00:03:49,760
Be.

50
00:03:51,400 --> 00:03:58,030
So here this is OC OC and temporary float is created.

51
00:03:58,480 --> 00:04:01,180
And this is actually the almost the same.

52
00:04:01,810 --> 00:04:12,090
And it's OC and the temporary float is created here actually in this, not in this line.

53
00:04:12,100 --> 00:04:16,870
In this line we have a OC and it called can compile successfully.

54
00:04:17,080 --> 00:04:22,900
And in F when we pass 1.0 as parameter, the temporary float is created.

55
00:04:22,900 --> 00:04:31,570
And then when we're going to pass the D as a parameter, the temporary float is clearly created as well

56
00:04:31,570 --> 00:04:38,350
here and we can pass the initialize our list list in this function here so you can pass, initialize

57
00:04:38,350 --> 00:04:44,220
our list as a parameter if that list can be converted to the type of the parameter.

58
00:04:44,230 --> 00:04:48,250
So for example, let's we're going to create the another struct here.

59
00:04:48,310 --> 00:04:53,060
Actually, we can delete this course and we can create another structure.

60
00:04:53,110 --> 00:04:54,520
We can delete this as well.

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Struct point.

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00:04:58,250 --> 00:05:07,910
Here this going take integer x here integer a or integer integer P here.

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Here.

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00:05:10,260 --> 00:05:16,050
So we're going to make the under function name set point.

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00:05:16,380 --> 00:05:19,630
And the point, as you can see, the point is a struct.

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00:05:19,650 --> 00:05:23,460
We're going to take the point struct as a parameter.

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00:05:24,700 --> 00:05:26,860
And name it Pete here.

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00:05:26,890 --> 00:05:31,390
So in the main function, we're going to code a point.

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00:05:31,390 --> 00:05:42,370
We're going to create a point object named P and reach the P dot A equals fun and P dot B equals one

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as well.

71
00:05:43,300 --> 00:05:45,820
And here we're going to set point.

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00:05:45,820 --> 00:05:54,310
We're going to use the set point function and we're going to pass to pass P as a parameter and we're

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00:05:54,310 --> 00:05:56,590
going to set point here.

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00:05:57,700 --> 00:05:59,470
Uh, using the color braces.

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00:05:59,950 --> 00:06:02,980
Your one and one here.

76
00:06:04,090 --> 00:06:09,980
And, uh, we're gonna return zero, as always, in the main function here.

77
00:06:10,000 --> 00:06:11,200
So.

78
00:06:12,910 --> 00:06:18,760
This code defines a structure that has two members here.

79
00:06:18,790 --> 00:06:21,110
Actually, let's make it look nice here like this.

80
00:06:21,130 --> 00:06:27,190
This structure has a two members, and in the main function, a new instance of point is created on

81
00:06:27,190 --> 00:06:32,430
the stack and it is initialized by accessing their members directly.

82
00:06:32,440 --> 00:06:38,170
So the instance is then passed to a function that has point parameters.

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00:06:38,170 --> 00:06:42,490
And since the parameter of set point here, set point is passed by value.

84
00:06:42,520 --> 00:06:48,310
The compiler creates a copy of the structure on the stack of the function here.

85
00:06:48,310 --> 00:06:51,780
And the second call of the set point does the same.

86
00:06:51,790 --> 00:06:58,480
The compiler will create a temporary point object on the stack of the function and initialize it with

87
00:06:58,480 --> 00:07:01,330
the values in the initialized list.