Display Patterns use Nested Loops

[LittleJava]

Hai i am newbie in java , can someone helpe me to get output like this :
Hoping can show some simple java source code by using nested Loop that is easy to understand. Many Thanks

1s Pattern:

1
2 4
3 6 9
4 8 12 16

2nd Pattern:

*
***
*****
***
*

3rd Pattern :

*****
*****
** **
*****
*****

4th Pattern:

*********
*********
*********
*********
...

[PhHein]

Just read my signature.

[SurfMan]

This cannot be done in Java. Java uses a binary system in powers of two, so odd numbers like 3 and 9 can't be created.

On a more serious note: ofcourse this can be done, but this is a forum, not a Code Factory™. Show your code and where you run into problems. We're here to help, not to spoonfeed you teh codez of the Jav.

[LittleJava]

This cannot be done in Java. Java uses a binary system in powers of two, so odd numbers like 3 and 9 can't be created.

On a more serious note: ofcourse this can be done, but this is a forum, not a Code Factory™. Show your code and where you run into problems. We're here to help, not to spoonfeed you teh codez of the Jav.

I am so sorry , i am never thought as this forum as Code Factory. Here we go this is my 1st try on the 1st pattern , where i learn that i can put a pattern 1 but as sequence 1 ,2 ,3 ... but how to change make it as multiplier.

public class Pattern{
        public static void main(String[]args){
            int i,j,k;

         for(i=0; i<4; i++) 
         {
             for (k=i+1; k<= 2*i+1; k++)
              {
                System.out.print( k % 10); 
              }
         System.out.println();
         }
       }
    }

[SurfMan]

The inner loop is wrong. You multiply by 2, but you need to multiply by i+1. Your code would be a bit more readable if you run your outer loop from 1: for( int i = 1; i <=4; i++ ). Now you can see exactly what its bounds are without having to resort to i+1 all the time. But again, that's merely my personal preference.

Here's the loop in calculated form:

(1*1)
(1*2) (2*2)
(1*3) (2*3) (3*3)
(1*4) (2*4) (3*4) (4*4)

See the pattern?

You also don't need the % operator. If your loops are correct, you only need to print i*k.

[LittleJava]

See the pattern?
You also don't need the % operator. If your loops are correct, you only need to print i*k.

thanks again , i see where i need to alter ,
This is 2nd pattern it should looks like diamonds , i am almost done it but i face some problems were the output looks like this :

         *
        ***
       *****
        ***
          *

class Pattern2 {
  public static void main(String[] args) {
    for (int i = 1; i <=6; i += 2) {
      for (int j = 0; j < 9 - i / 2; j++)
        System.out.print(" ");

      for (int j = 0; j < i; j++)
        System.out.print("*");

      System.out.print("\n");
    }

    for (int i = 3; i > 0; i -= 2) {
      for (int j = 0; j < 5 - i / 2; j++)
        System.out.print("  ");

      for (int j = 0; j < i; j++)
        System.out.print("*");

      System.out.print("\n");
    }
  }
}

[harshit shah]

your 4th pattern is easy:

public class pattern_4
{
    public static void p4(int n)
    {
        int i;
        for(i=1;i<=n;i++)
        {
            System.out.println("*********");
        }
    }
}

[harshit shah]

your 2nd pattern:

public class pattern_2
{
    public static void p2()
    {
        int i,j;
        for(i=1;i<=6;i+=2)
        {
            for(j=1;j<=i;j++)
            {
                System.out.print("*");
            }
            System.out.println();
        }
        i=1;
        for(i=1;i<=4;i+=2)
        {
            for(j=3;j>=i;j--)
            {
                System.out.print("*");

            }
            System.out.println();
        }
    }
}

[SurfMan]

your 2nd pattern:

public class pattern_2
...
}

Although the OP probably will with no doubt appreciate your hard work, it's still *his* assignment for school that your are doing *for* him. Don't spoonfeed homeworkers here. It's an assignment for a reason.

[JosAH]

@harshit shah: spoonfeeding is not allowed here (and neither in a lot of other technical forums); because I'm such a nice guy I'll let you get away with it but rumours say that other moderators exist who'd love to shred you in the... shudder... rotating-knives machine before banning your remains ...

kind regards,

Jos

[LittleJava]

I am really appreciate , all the help but i am prefer do from scratch on my own. i post it just as a reference where i can make even more. so the 2nd pattern i do with this way.

    import java.util.Scanner;  
      
    public class Square {  
    public static void main(String[] args)  
        {  
      
            Scanner input = new Scanner(System.in);  
      
            System.out.println("Welcome! This program will take your\n" +  
                               "number input, and generate a square \n" +  
                               "of stars.\n");
                                 
            System.out.print("Please enter a number: ");  
            int number = input.nextInt();  
      
            for (int i=1; i<=number; i++)  
            {  
                for (int j=1; j<=number; j++)
                	  
                System.out.print("*");  
                System.out.println();  
            }  
        }  
    }

[LittleJava]

Now i am moving on to another code , which is using math formula. i got the basic but i got this error keep bugging me. Really don't know what wrong with my code, hoping someone can tell which part that i am do wrong.

   import java.util.Scanner;

public class Area
 {

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

System.out.print("Enter first two points (x1, y1) :");
double x1 = input.nextDouble();
double y1 = input.nextDouble();

System.out.print("Enter second two points (x2, y2) :");
double x2 = input.nextDouble();
double y2 = input.nextDouble();

double distance = Math.pow(((x2 - x1)(x2 - x1) + (y2 - y1)(y2 - y1)), 0.5);

System.out.print("The distance of the two points is " + distance);
}
}

The Error at the line 17 which is unexpected type. how to solve this problem.

[JosAH]

@LittleJava: Don't indent your code like that: the second System.out.println() statement doesn't belong to the inner loop while the indentation suggests otherwise.

kind regards,

Jos

ps. w.r.t. your next reply: Java doesn't know about implicit multiplication signs.

[Ronin]

Java doesn't quite understand the mathematical notation on line 17.
(x2 - x1)(x2 - x1) should be rewritten to ((x2 - x1)*(x2 - x1)). This also applies to the second half of the equation.

Regards.

[LittleJava]

Java doesn't quite understand the mathematical notation on line 17.
(x2 - x1)(x2 - x1) should be rewritten to ((x2 - x1)*(x2 - x1)). This also applies to the second half of the equation.

Regards.

I try to do just what you suggest but when its compile no problems

double distance = Math.pow((((x2 - x1)*(x2 - x1)) + ((y2 - y1)*(y2 - y1))), 0.5);

The Output shown like this :

Usage: java [-options] class [args...]
           (to execute a class)
   or  java [-options] -jar jarfile [args...]
           (to execute a jar file)
where options include:
    -d32	  use a 32-bit data model if available
    -d64	  use a 64-bit data model if available
    -server	  to select the "server" VM
    -hotspot	  is a synonym for the "server" VM  [deprecated]
                  The default VM is server.

    -cp <class search path of directories and zip/jar files>
    -classpath <class search path of directories and zip/jar files>
                  A ; separated list of directories, JAR archives,
                  and ZIP archives to search for class files.
    -D<name>=<value>
                  set a system property
    -verbose:[class|gc|jni]
                  enable verbose output
    -version      print product version and exit
    -version:<value>
                  require the specified version to run
    -showversion  print product version and continue
    -jre-restrict-search | -no-jre-restrict-search
                  include/exclude user private JREs in the version search
    -? -help      print this help message
    -X            print help on non-standard options
    -ea[:<packagename>...|:<classname>]
    -enableassertions[:<packagename>...|:<classname>]
                  enable assertions with specified granularity
    -da[:<packagename>...|:<classname>]
    -disableassertions[:<packagename>...|:<classname>]
                  disable assertions with specified granularity
    -esa | -enablesystemassertions
                  enable system assertions
    -dsa | -disablesystemassertions
                  disable system assertions
    -agentlib:<libname>[=<options>]
                  load native agent library <libname>, e.g. -agentlib:hprof
                  see also, -agentlib:jdwp=help and -agentlib:hprof=help
    -agentpath:<pathname>[=<options>]
                  load native agent library by full pathname
    -javaagent:<jarpath>[=<options>]
                  load Java programming language agent, see java.lang.instrument
    -splash:<imagepath>
                  show splash screen with specified image
See http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.

Process completed.

I am using JCreator 5.0. The source Code problem or my compiler ?

[harshit shah]

@harshit shah: spoonfeeding is not allowed here (and neither in a lot of other technical forums); because I'm such a nice guy I'll let you get away with it but rumours say that other moderators exist who'd love to shred you in the... shudder... rotating-knives machine before banning your remains ...

kind regards,

Jos

let the shredding begin.
++++ [NOW I AM LITTLE SHAMELESS. i.e. fuberable decremented me by 2x for loop with -- function.]