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[Zulf]

This is my like, first ever tutorial I've ever written, so it might be horrible. :P

Well, this tutorial is going to be on splitting strings and getting the data and use it

for multiple things, the tutorial is very short and I will expand it soon.

TABLE OF CONTENTS:
• What splitting(parsing) can be used for
• Where to start - Getting user input
• How to split a string and convert to integers to do math problems

Part 1, What splitting(parsing) can be used for:

You can use this for using 2 numbers in a string to add together, or multiple

numbers.
You can use this if you make a 2d game, such as a maze to make a 'custom maze-

making system.'

Part 2, Where to start - Getting user input:

You should start by having your blank Java document:

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public class Main {

    public static void main(String[] args) {

    }

}

What this does:
The 'main' method is static and it tells the Java engine which file to

initialize first.

You then need to import the scanner from 'java.util.Scanner' by using this code:

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import java.util.Scanner;

and adding that to the beginning of the file, you should now have this:

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import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

    }

}

Now you must create a Scanner to make it useable, by adding this code to the Document:

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Scanner s = new Scanner(System.in);

What this does:
s = Scanner name
System.in = allows the scanner to grab the text entered in console.

To start you need to add a message to let the user know he/she should enter some text into

the console:

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System.out.println("Enter a string:");

Once the string is entered you must create a variable(String) and let the string carry

what text the scanner has grabbed:

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String str;
str = s.nextLine();
System.out.println("You have entered: " + str);

What this does:
str = String variable
type: String (allows you to hold text data)
println = Just lets the user know what they entered by printing the

string, 'str' to the console.
s.nextLine = grabs the text and starts a new line.

We are done with this section of the tutorial. Your code should look similar to this:

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import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
	Scanner s = new Scanner(System.in);
	System.out.println("Enter a string:");
	String str;
	str = s.nextLine();
	System.out.println("You have entered: " + str);
    }

}

Part 3, How to split a string and convert to integers to do math problems:

Now you have your code from the last section of this tutorial so we're ready to use that

tutorial to allow users to do math problems and such.

To start, you should change the text to notify users to type something used in part 2 with

this:

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System.out.println("Enter a set of numbers(x,x);"); //dont include the ( or )

Next, we need to split the string 'str' into useable format by using this code:

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String[] str0 = str.split(",");
String num1 = str0[0];
String num2 = str0[1];

What this does:
str0 = an array used to keep entered text, minus the split, ','.
num1 = a string used to keep the first number BEFORE the comma
num2 = a string used to keep the first number AFTER the comma

Why to split by a comma?:
We split by a comma because the format text should be entered is (x,x)

where x is an integer(I hope so).

Now that we have the numbers from the text, we need to convert them into useable types,

such as Integers for math problems:

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int num1_0;
int num2_0;
num1_0 = Integer.parseInt(num1);
num2_0 = Integer.parseInt(num2);

Now that we have the split string pieces into correct types to use for math problems we

need to add the code:

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int add, subt, mult, div;
add = num1_0 + num2_0;
subt = num1_0 - num2_0;
mult = num1_0 * num2_0;
div = num1_0 / num2_0;

Now that we have the results for the math problems, we need to print them so the user can

see:

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System.out.println("Addition: " + add);
System.out.println("Subtraction: " + subt);
System.out.println("Multiplication: " + mult);
System.out.println("Division: " + div);

Now once you've added that you're all done!

Your final code should look like this:

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import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
	Scanner s = new Scanner(System.in);
	System.out.println("Enter a set of numbers(x,x);"); //dont include the ( or )
	String str;
	str = s.nextLine();
	System.out.println("You have entered: " + str);
	String[] str0 = str.split(",");
	String num1 = str0[0];
	String num2 = str0[1];
	int num1_0;
	int num2_0;
	num1_0 = Integer.parseInt(num1);
	num2_0 = Integer.parseInt(num2);
	int add, subt, mult, div;
	add = num1_0 + num2_0;
	subt = num1_0 - num2_0;
	mult = num1_0 * num2_0;
	div = num1_0 / num2_0;
	System.out.println("Addition: " + add);
	System.out.println("Subtraction: " + subt);
	System.out.println("Multiplication: " + mult);
	System.out.println("Division: " + div);
    }

}

Your output should look something like this:

(The reason division is 0 is because it would come out as a decimal(double in Java) and int's only hold whole numbers, so to get the decimal of the math problem, you would need to convert it to a double, not an int.

Thank you for reading my tutorial, if anything is unclear, or you think I did not explain a bit well then please post so I can help you learn more.

[Axel]

Java !=Javascript;
bump();

[mikethedj4]

Wrong section bro!