Adding 2 Number In Java

[LOVE4EVER]

HI PPL

I DID A SIMPLE PROGRAM THAT ADD 2 NUMBER BUT I AM HAVING PROBLEM IN ENTER THE NUMBER FROM THE USER

import java.io.*;
public class cal{


int a=0;
int b=0;
int c=0;


a =reader.readLine();
b =reader.readLine();
c =a+b;
system.out.println(c);
}

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>
the error in the reader.readline ();

in c++ you just have to write cin>>a>>

i am new in java and i really dont know what to do

[sukatoa]

HI PPL

I DID A SIMPLE PROGRAM THAT ADD 2 NUMBER BUT I AM HAVING PROBLEM IN ENTER THE NUMBER FROM THE USER

import java.io.*;
public class cal{


int a=0;
int b=0;
int c=0;


a =reader.readLine();
b =reader.readLine();
c =a+b;
system.out.println(c);
}

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>
the error in the reader.readline ();

in c++ you just have to write cin>>a>>

i am new in java and i really dont know what to do

Welcome to java forum.... :)

You can start to read Scanner class.

Look for Scanner( inputstream s) Constructor.... .

Read also about "System.in" , " Integer.parseIn t( String s ) ".....
try to browse again about object and class in java on how they will be used...

Try to have some experiment on this

Scanner scan = new Scanner(System.in);
String num1 = scan.nextLine();
int integervalue = Integer.parseInt( num1 );

Don't forget to import the built-in Scanner class....

Update us...
sukatoa

[LOVE4EVER]

thx for the information a lot sukatoa its really helped me

now the code is like this

import java.io.*;
import java.util.Scanner;
public class cal{



Scanner read = new Scanner(system.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
system.out.println(c);
}

there are 2 errors
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>
cal.java:12: <identifier> expected
system.out.prin tln(c);
^
cal.java:12: <identifier> expected
system.out.prin tln(c);
^
2 errors
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>
how (c) can be identifier!!!

[sukatoa]

thx for the information a lot sukatoa its really helped me

now the code is like this

import java.io.*;
import java.util.Scanner;
public class cal{



Scanner read = new Scanner(system.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
system.out.println(c);
}

there are 2 errors
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>
cal.java:12: <identifier> expected
system.out.prin tln(c);
^
cal.java:12: <identifier> expected
system.out.prin tln(c);
^
2 errors
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>
how (c) can be identifier!!!

You forgot to change the "s". It should be System.

Just a reminder bro: Java is case sensitive.... :)

regards,
sukatoa....

[Laharl]

Also, you don't need to import java.io.*, since the Scanner is handling input and System.out.prin tln handles output (the System class is included by default). Imports are like C(++)'s #includes, if you're not using anything from them, don't import/#include them. It's not a huge deal now, but it's just good practice not to import more than you need, as it slows down your code (especially if you import java.*...or javax.*...).

[LOVE4EVER]

i did all the things you told me guys but i am still having the same errors

this is the the new code

import java.util.Scanner;
public class cal{

Scanner read = new Scanner(System.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
System.out.println (c);
}

2 errors
>>>>>>>>>>>>>>> >>>>>>>>>
Exception in thread "main" java.lang.NoCla ssDefFoundError : cal
Caused by: java.lang.Class NotFoundExcepti on: cal
at java.net.URLCla ssLoader$1.run( URLClassLoader. java:200)
at java.security.A ccessController .doPrivileged(N ative Method)
at java.net.URLCla ssLoader.findCl ass(URLClassLoa der.java:188)
at java.lang.Class Loader.loadClas s(ClassLoader.j ava:306)
at sun.misc.Launch er$AppClassLoad er.loadClass(La uncher.java:276 )
at java.lang.Class Loader.loadClas s(ClassLoader.j ava:251)
at java.lang.Class Loader.loadClas sInternal(Class Loader.java:319 )

C:\DOCUME~1\mes \java>javac cal.java
cal.java:9: <identifier> expected
System.out.prin tln (c);
^
cal.java:9: <identifier> expected
System.out.prin tln (c);
^
2 errors

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>

[JosAH]

Take a Java tutorial before you start banging your keyboard: Java classes have
methods and methods have statements. You can't put statements just at the
class level, i.e. it doesn't make sense to the compiler.

kind regards,

Jos

[sukatoa]

i did all the things you told me guys but i am still having the same errors

this is the the new code

import java.util.Scanner;
public class cal{

Scanner read = new Scanner(System.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
System.out.println (c);
}

2 errors
>>>>>>>>>>>>>>> >>>>>>>>>
Exception in thread "main" java.lang.NoCla ssDefFoundError : cal
Caused by: java.lang.Class NotFoundExcepti on: cal
at java.net.URLCla ssLoader$1.run( URLClassLoader. java:200)
at java.security.A ccessController .doPrivileged(N ative Method)
at java.net.URLCla ssLoader.findCl ass(URLClassLoa der.java:188)
at java.lang.Class Loader.loadClas s(ClassLoader.j ava:306)
at sun.misc.Launch er$AppClassLoad er.loadClass(La uncher.java:276 )
at java.lang.Class Loader.loadClas s(ClassLoader.j ava:251)
at java.lang.Class Loader.loadClas sInternal(Class Loader.java:319 )

C:\DOCUME~1\mes \java>javac cal.java
cal.java:9: <identifier> expected
System.out.prin tln (c);
^
cal.java:9: <identifier> expected
System.out.prin tln (c);
^
2 errors

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>

Those error may be avoided if you put those codes inside a method....
You forgot also to have main method....

Jos' recommendation may lead you to the right way....

After reading, applying what you've learn,

Update us about your new code.....
sukatoa...

[LOVE4EVER]

i talled you guys i am new in java i used to programming in c++ and when i did
this very simple program i was using my information about c++ but never mind i didnt copy this problem without reading java tutorial but maybe you are see it simple problem for you but for me its not and i did a program that compute the result without the user enter the number but any way thx for help and the information its really helpful and of cource in the final i will have a code without errors

[JosAH]

i talled you guys i am new in java i used to programming in c++ and when i did
this very simple program i was using my information about c++ [ ... ]

C++ (and C and BCPL and CPL and C#) also have statements in functions/methods only.
Java is no exception. Please don't imagine how a language could/should work,
read the authorative standards on it and only then try to implement something.
Even more: before you implement anything at all you should design it first, just
using scrapbook paper and a pencil. The actual typing in of your program should
be a boring task and should be finished asap.

Most people don't do that: they have a vague idea and they start banging their
keyboards with the only result that they're tied to that damned thing during long
complicated debug sessions until 'something' more or less working is the result.
Don't follow that path because all you'll create are ugly little monstrosities.

kind regards,

Jos

[LOVE4EVER]

i understant now why the errors because there is no method so i put the method and its really nice to see that no errors in the code but when i open the .class file it give me this statment
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>

Exception in thread "main" java.lang.NoSuc hMethodError: main

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>

and this is the code

import java.util.Scanner;
public class cal{

public static void main(int  [] args) 
{
Scanner read = new Scanner(System.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
System.out.println(c);
}
}

why its not working ?

[JosAH]

i understant now why the errors because there is no method so i put the method and its really nice to see that no errors in the code but when i open the .class file it give me this statment
>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>

Exception in thread "main" java.lang.NoSuc hMethodError: main

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>

and this is the code

import java.util.Scanner;
public class cal{

public static void main(int  [] args) 
{
Scanner read = new Scanner(System.in);

int a =read.nextInt();
int b =read.nextInt();
int c =a+b;
System.out.println(c);
}
}

why its not working ?

The single argument to the main() method has type String[] not int[]. The JVM
checks that.

kind regards,

Jos

[hsn]

you should also look at other types to read any input like InputStreamRead er and so.

hsn

[BigDaddyLH]

I still think going through a tutorial could only help you.

[Kid Programmer]

HI PPL

I DID A SIMPLE PROGRAM THAT ADD 2 NUMBER BUT I AM HAVING PROBLEM IN ENTER THE NUMBER FROM THE USER

import java.io.*;
public class cal{


int a=0;
int b=0;
int c=0;


a =reader.readLine();
b =reader.readLine();
c =a+b;
system.out.println(c);
}

>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>
the error in the reader.readline ();

in c++ you just have to write cin>>a>>

i am new in java and i really dont know what to do

You are becoming a help vampire. But to get this over with just copy and paste this code:

import java.util.Scanner;

public class cal {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		double a, b, c;
	
		a = scan.nextDouble();
		b = scan.nextDouble();
		c = a + b;

		System.out.println(c);
	}
}

It should work perfectly :-) Good luck programming.