Printing pyramid pattern out of characters

Question

I need to print an array of characters in a pyramid shape. What I have so far is this:

char[] chars = {'F', 'E', 'L', 'I', 'Z', ' ', 'A', 'N','I', 'V', 'E', 'R', 'S', 'A', 'R', 'I', 'O'};
    int length = chars.length;


  for (int i = 1; i < length; i += 2) {
  for (int j = 0; j < 9 - i / 2; j++)
    System.out.print(" ");

  for (int j = 0; j < i; j++)
    System.out.print(chars[j]);

  System.out.print("\n");
}
  for (int i = length; i > 0; i -= 2) {
  for (int j = 0; j < 9 - i / 2; j++)
    System.out.print(" ");

  for (int j = 0; j < i; j++)
    System.out.print(chars[j]);

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

and it prints this:

           F
          FEL
         FELIZ
        FELIZ A
       FELIZ ANI
      FELIZ ANIVE
     FELIZ ANIVERS
    FELIZ ANIVERSAR
   FELIZ ANIVERSARIO
    FELIZ ANIVERSAR
     FELIZ ANIVERS
      FELIZ ANIVE
       FELIZ ANI
        FELIZ A
         FELIZ
          FEL
           F

But I need it to start printing from the character in the middle of the array. The end result gotta be like this:

                       I
                      NIV
                     ANIVE
                    ANIVER
                   Z ANIVERS
                  IZ ANIVERSA
                 LIZ ANIVERSAR
                ELIZ ANIVERSARI
               FELIZ ANIVERSARIO
                ELIZ ANIVERSARI
                 LIZ ANIVERSAR
                  IZ ANIVERSA
                   Z ANIVERS
                    ANIVER
                     ANIVE
                      NIV
                       I

Any help would be greatly appreciated.

Answer 1

You can do the same thing as show on below code. It will use lesser number of for loops. I have added inline comments in the code go through it.

    char[] chars = { 'F', 'E', 'L', 'I', 'Z', ' ', 'A', 'N', 'I', 'V', 'E', 'R', 'S', 'A', 'R', 'I', 'O' };
    int length = chars.length;


    for (int line=0;line<=length;line++) {
        //This will print upper part of pyramid
        if(line < length/2){
            String output="";
            int middelVal=length/2;
            for (int i = middelVal - line; i > 0; i--) {
                output=output+" ";
            }
            for (int i = middelVal - line; i <= middelVal + line; i++) {
                output=output+chars[i];
            }
            System.out.println(output);
        }else if(line > length/2){
            //This will print lower part of pyramid
            String output="";
            int middelVal=length/2;
            int nwNum = chars.length-line;
            for (int i = middelVal - nwNum; i > 0; i--) {
                output=output+" ";
            }
            for (int i = middelVal - nwNum; i <= middelVal + nwNum; i++) {
                output=output+chars[i];
            }
            System.out.println(output);
        }
    }

Answer 2

Here is another approach using 2d array

    char[] chars = { 'F', 'E', 'L', 'I', 'Z', ' ', 'A', 'N', 'I', 'V', 'E', 'R', 'S', 'A', 'R', 'I', 'O' };
    int size = chars.length;
    int mid = size / 2 + 1;
    char[][] matrix = new char[size][size];
    for (char[] cs : matrix) {
        Arrays.fill(cs, ' ');
    }
    for (int i = 0; i < size; i++) {
        int l = Math.abs(mid - 1 - i);
        int r = size - l;
        for (int m = l; m < r; m++) {
            matrix[i][m] = chars[m];
        }
    }
    for (char[] cs : matrix) {
        System.out.println(cs);
    }

output

        I        
       NIV       
      ANIVE      
      ANIVER     
    Z ANIVERS    
   IZ ANIVERSA   
  LIZ ANIVERSAR  
 ELIZ ANIVERSARI 
FELIZ ANIVERSARIO
 ELIZ ANIVERSARI 
  LIZ ANIVERSAR  
   IZ ANIVERSA   
    Z ANIVERS    
      ANIVER     
      ANIVE      
       NIV       
        I