Difference between revisions of "Java/C2/Nested-if/English-timed"
From Script | Spoken-Tutorial
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|Operand 1 is the value of the variable Result if the condition is true. | |Operand 1 is the value of the variable Result if the condition is true. | ||
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− | | | + | |07:03 |
|Operand 2 is the value if the condition is false. | |Operand 2 is the value if the condition is false. | ||
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| Now Let us use it in our program. | | Now Let us use it in our program. | ||
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− | | 07:12 | + | |07:12 |
− | | | + | |First let us remove the if-else statement. |
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| 07:17 | | 07:17 | ||
− | | | + | |Type '''nHalf = n % 2 == 0 ? n / 2 : (n + 1) / 2''' semi-colon |
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− | | | + | |07:41 |
|This statement reads, | |This statement reads, | ||
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|if n is even, nHalf is n by 2 ,Otherwise, it is n plus 1 by 2. | |if n is even, nHalf is n by 2 ,Otherwise, it is n plus 1 by 2. | ||
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− | | | + | |07:50 |
− | | | + | |Let us now see it in action. |
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− | | | + | | As we can see, the output is as expected. |
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|This way, ternary operator reduces clutter in the code and improves readability. | |This way, ternary operator reduces clutter in the code and improves readability. | ||
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| We have come to the end of this tutorial. | | We have come to the end of this tutorial. | ||
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− | | | + | |08:22 |
− | + | |Now take an assignment on | |
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|Nested-If and Ternary operator. Write java program for the following. | |Nested-If and Ternary operator. Write java program for the following. | ||
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| '''Spoken Tutorial '''Project is a part of the '''Talk to a Teacher''' project and | | '''Spoken Tutorial '''Project is a part of the '''Talk to a Teacher''' project and | ||
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− | | | + | | 09:11 |
− | |It is supported by the '''National Mission on Education through ICT, MHRD, Government of India. |- | + | |It is supported by the '''National Mission on Education through ICT, MHRD, Government of India. |
+ | |- | ||
| 09:17 | | 09:17 | ||
||'''More information on this Mission is available at '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro''' | ||'''More information on this Mission is available at '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro''' |
Revision as of 12:42, 5 June 2013
Time | Narration |
00:02 | Welcome to the spoken tutorial on Nested-If and Ternary Operator in java. |
00:07 | By the end of this tutorial you should be able to:
|
00:17 | For this tutorial we are using:
Ubuntu v 11.10, JDK 1.6,and EclipseIDE 3.7.0 |
00:27 | To follow this tutorial, you should know, |
00:29 | about the usage of relational and logical operators. |
00:33 | And if...else control flow statements. |
00:36 | If not, for relevant tutorial please visit our website which is as shown. |
00:41 | Nested if statements an If statement within another if statement is called a nested-if statement. |
00:49 | Now let us locate the syntax for writing the Nested-If statement. |
00:53 | In this case, if condition 1 is true, then the program checks for condition 2. |
00:59 | Condition 2 is given using another If statement. |
01:03 | condition 2 is true, then the program executes Statement or block 1. |
01:09 | Else, it executes Statement or block 2.
|
01:13 | If condition 1 is false, then the program will not check condition2. |
01:18 | Instead it will directly jump to its else statement i.e. block 3. |
01:24 | nOw Let us try and example to understand that better |
01:28 | We have the eclipse IDE and the skeleton required for the rest of the code. |
01:32 | We have created a class NesedIfDemo and added the main method to it. |
01:37 | We shall check if the given number is a even number or an odd number. |
01:42 | we will also handle negative numbers using a nested-if. |
01:46 | So inside the main method type |
01:49 | int n = minus 5; |
01:54 | We have created a variable n to store the negative number. |
01:58 | Now we shall write the if conditions. |
02:01 | Next line Type |
02:02 | if (n < 0) |
02:07 | open curly bracket. Press enter |
02:10 | System.out.println Within brackets and double quotes (“Negative number”); |
02:22 | We first see if the number is a negative number. |
02:25 | If yes then we will not check for even and odd. |
02:29 | if the number is not a negative, we check for even and odd. |
02:34 | Next line Type
else { } Press enter |
02:42 | Now if the execution has come to the else part. |
02:45 | It means that the number is non negative.
|
02:48 | So we check for odd or even inside this else part. |
02:52 | Type |
02:53 | if (n modules 2 double equal to 0) { Press enter |
03:03 | System.out.println(“Even number”);
} else { press enter Type System.out.println(“Odd number”); } |
03:29 | So we make sure that negative numbers are not considered for odd or even check. |
03:34 | Now let us see the code in action. |
03:37 | Save and run the file.As we can see, we get the output as“negative number”. |
03:43 | now Let us try a positive number |
03:46 | Change n = -5 to n = 5 |
03:53 | NowSave and Run the file |
03:57 | As we can see, the output is odd number as expected. Let us try an even number |
04:04 | Change n = 5 to n = 10. |
04:09 | Now Save and run the file |
04:12 | As we can see, the output is “even” number as expected. |
04:17 | This process of including an if statement inside another, is called nested-if. |
04:22 | There is no limit to the amount of nesting. |
04:25 | But it is a good practice to not go beyond 3 levels of nesting. |
04:31 | Now we shall look at the ternary operator. |
04:33 | First let me clean up the Main method. |
04:37 | We shall write a program that divides a number by 2. |
04:40 | It is a very trivial program but the issue comes in dividing odd numbers. |
04:45 | When 7 is divided by 2, we get 3. |
04:48 | But what if we want the result to be rounded off. |
04:50 | Which means, when 7 is divided by 2, we get 4 and not 3 |
04:56 | In simple terms, we need the next number. |
04:59 | Let us see how to write such a program. |
05:01 | See inside the main method Type int n, nHalf ; |
05:08 | We will store the number in n and the half number in nHalf |
05:13 | NExt line Type n = 5; |
05:18 | NExt line Type if (n % 2 == 0) { Press enter |
05:28 | Type nHalf = n / 2;
} else { nHalf = (n + 1) / 2; } |
05:50 | We check if the number is even or odd and do the division accordingly. |
05:55 | Now Let us add a print statement to see the program in action. |
05:59 | So Type System.out.println(nHalf); |
06:11 | Now Save and Run the file
|
06:14 | As we can see, our objective is met. We get the output as 3 and not 2 |
06:21 | But if we notice, all we are doing is, setting the value of a variable depending on a condition.
|
06:27 | There is more syntax than logic in our program.
|
06:31 | This is when ternary operator makes code simpler. |
06:35 | Ternary Operator conditional operator providing results similar to nested-if. |
06:40 | It Provides a short syntax and is denoted by a question mark. |
06:45 | It Takes three operands at a time. |
06:48 | Let us learn about the syntax of Ternary Operator.
|
06:53 | The expression is the condition that has to be checked.
|
06:56 | Operand 1 is the value of the variable Result if the condition is true.
|
07:03 | Operand 2 is the value if the condition is false. |
07:09 | Now Let us use it in our program. |
07:12 | First let us remove the if-else statement. |
07:17 | Type nHalf = n % 2 == 0 ? n / 2 : (n + 1) / 2 semi-colon
|
07:41 | This statement reads, |
07:43 | if n is even, nHalf is n by 2 ,Otherwise, it is n plus 1 by 2. |
07:50 | Let us now see it in action. |
07:52 | Save and Runthe file. Press Ctrl S and Ctrl F11 keys |
07:59 | As we can see, the output is as expected.
|
08:02 | This way, ternary operator reduces clutter in the code and improves readability. |
08:09 | We have come to the end of this tutorial. |
08:11 | In this tutorial we have learnt: |
08:13 | * About Nested-If Statements and Ternary Operator |
* Usage of Nested-If Statements and Ternary Operator in a Java program | |
08:22 | Now take an assignment on |
08 :23 | Nested-If and Ternary operator. Write java program for the following. |
08:28 | * Check whether a number is even and also a multiple of 11 using nested-if. |
08:34 | * Identify the largest number among the two given numbers using Ternary operator.
|
08:40 | To know more about the Spoken Tutorial project, watch the video available at the following link. |
08:45 | It summarizes the spoken-tutorial project.If you do not have good bandwidth, you can download and watch it. |
08:52 | The Spoken Tutorial Project Team. |
08:54 | Conducts workshops using spoken tutorials and |
08:57 | gives certificates for those who pass an online test. For more details, please write to contact AT spoken HYPHEN tutorial DOT org. |
09:07 | Spoken Tutorial Project is a part of the Talk to a Teacher project and |
09:11 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
09:17 | More information on this Mission is available at spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro |
09:26 | This script has been contributed by TalentSprint. This is Arya Ratish from IIT Bombay signing off. Thanks for joining. |
Contributors and Content Editors
Arya Ratish, Devisenan, Krupali, PoojaMoolya, Priyacst, Sandhya.np14, Sneha