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Thread: Trying to create Triangles with Characters and Spaces

  1. #1
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    Question Trying to create Triangles with Characters and Spaces

    So I am trying to create this with my program:
    AAAAAAAA
    AAAAAAA
    AAAAAA
    AAAAA
    AAAA
    AAA
    AA
    A
    I am supposed to import the number of rows and the characters from a data file.
    Here is the code I wrote for it:

    import java.util.*;
    import java.io.*;
    public class Lab11d {
    public static void main(String []args) throws IOException
    {
    Scanner input = new Scanner(new File("Lab11d.dat"));
    while(input.next().equals("y"))
    {
    int row = input.nextInt();
    char col = input.next().charAt(0);
    String output = "";
    for(int i = row; i>0; i--)
    {
    for(int j = i; i>0;j--)
    {
    if(j==row)
    {
    output+="";
    continue;
    }
    else
    output+=" ";
    }
    for(int k = row; k>0; k--)
    output+=col;
    }
    System.out.println(output);
    }
    }
    }

    Here is the data file:
    8 A
    2 B
    1 T
    3 B


    I don't have any errors that Eclipse found. When I run it, nothing is printed in the console. Does anyone have any suggestions?


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    Default Re: Trying to create Triangles with Characters and Spaces

    The spaces are supposed to be on the left side of the characters for the output.

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    Cool Re: Trying to create Triangles with Characters and Spaces

    try this piece of code I just made...Might help..:
    PHP Code:
    import java.io.*;
    public class 
    p_no3{
          public static 
    void main(String[] args){
          
    int e;
          
    int j;
          for (
    e=9;e>=1;e--){
               for(
    j=e;j>=1;j--){
               
    System.out.print ("A");}
                 
    System.out.println (" ");
               }
         }


  4. The Following User Says Thank You to XxClouDxX For This Useful Post:

    MJtechie12 (December 19th, 2011)

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    Default Re: Trying to create Triangles with Characters and Spaces

    Thank you! Your code works perfectly but unfortunately I need the spaces to be on the other side of the A. It would look like this except with spaces instead of underscores:
    AAAAA
    _AAAA
    __AAA
    ___AA
    ____A

    And I also need to know why it won't read my data file.

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    Default Re: Trying to create Triangles with Characters and Spaces

    Quote Originally Posted by XxClouDxX View Post
    try this piece of code I just made...Might help..:
    XxClouDxX, please read the forum rules as well as the following
    The Problems With Spoonfeeding


    MJtechie12, please wrap your code in the code tags. Since you've already been handed a partial answer, what did you try to move the spaces to the other side?

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    Default Re: Trying to create Triangles with Characters and Spaces

    I've now done this:
    PHP Code:
    import java.io.*; 
    public class 
    test
          public static 
    void main(String[] args){ 
          
    int e
          
    int j
          
    int k;
          
    String output "";
          for (
    e=9;e>=0;e--){ 
              for(
    k=ek>=e-1k-=1)
                  if(
    e==9)
                      
    k=e+1;
                  else
                      
    output+=" ";
              for(
    j=k+ej<e;j++) 
                 
    output+="A";
               
    output+="\n";
           
          }
          
    System.out.println(output);
      }

    And now it won't output anything.

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    Default Re: Trying to create Triangles with Characters and Spaces

    And now it won't output anything.
    Add some println's in there to debug and see which loops are being executed and perhaps which are not, use this technique to break the problem down. Programming is a workflow that requires several rounds of modification, printing debug statements, compiling and running.

    for(j=k+e; j<e;j++)

    Think very carefully about this logic - when will j=k+e ever be less than e?

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    Default Re: Trying to create Triangles with Characters and Spaces

    Another technique that will help you understand what your code is to do is to use variable names with meanings. You app is working with rows and columns and the number of spaces on a row and the number of characters on a row. If you were to name your variables with appropriate names then reading the code would help you understand what the code is doing.

    What are e, k and j. Something like: Row, column and number of char?

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