[solved] Pick random #'s, shuffle 2d array;errors,invalid conversion

Projects Programming
1

So I have a compiler error and I don't know what to do with it. The error is below.

LCDArrayStylesEDIT.ino: In function 'int randomWriteArray2(char (*)[16])':
LCDArrayStylesEDIT:135: error: invalid conversion from 'int*' to 'int'
LCDArrayStylesEDIT:136: error: invalid types 'int [2][int [16]]' for array subscript

This function basically shuffles an array initialized with integers to generate a random pick.

orderCols[][] gets filled with 0 to cols-1, it's shuffled.
orderRows[] gets filled with 0 to rows-1, it's shuffled.
I then iterate over an array with chars called LCDarray[][] to print to the randomized locations by picking elements from LCDarray and placing them in the correct spot on the LCD with the values in the shuffled arrays.
Once orderRows[] is used completely it's reinitialized and shuffled to get more random picks until all cols are printed.

//pertinent declarations
#include <LiquidCrystal.h>
#define cols 16
#define rows 2
char LCDarray[rows][cols];

int randomWriteArray2(char LCDarray[][cols]){
  int j=0, k=0, r=0, temp=0;
  int orderCols[rows][cols];
  int orderRows[rows];
  //randomSeed(time);
  
  //fill orderCols with "0 to cols-1" for all rows
  for(j=0;j<rows;j++){
    for(k=0;k<cols;k++){
      orderCols[j][k]=k;
    }
  }
  
  //randomize orderCols
  for(j=0;j<rows;j++){
    for (k=0;k<cols;k++){
    r=random(cols);//pick random number from 0-cols
    temp=orderCols[j][k];//temp of swap area
    orderCols[j][k]=orderCols[j][r];//swap in selected number
    orderCols[j][r]=temp;//save temp number
    }
  }
  
  //fill orderRows with "0 to rows-1"
  for(k=0;k<rows;k++)orderRows[k]=k;
  //randomize elements
  for(k=0;k<cols;k++){
    r=random(rows);//pick random number from 0-cols
    temp=orderRows[k];//temp of swap area
    orderRows[k]=orderRows[r];//swap in selected number
    orderRows[r]=temp;//save temp number
  }

  //print by randomizing order rows each time and printing all cells in order
  int column,row;//extra variables for temporary readability
  for(j=0;j<cols;j++){
    for(k=0;k<rows;k++){
      column=orderCols[k];
      row=orderRows[orderCols[k]][k];
      lcd.setCursor(column, row);
      lcd.write(LCDarray[row][column]);
      delay(100);
    }
    //rerandomize row pick
    for(k=0;k<rows;k++)orderRows[k]=k;
    for(k=0;k<cols;k++){
      r=random(rows);//pick random number from 0-cols
      temp=orderRows[k];//temp of swap area
      orderRows[k]=orderRows[r];//swap in selected number
      orderRows[r]=temp;//save temp number
    }
  }
  wipeArray(LCDarray);
  return 0;
}
2

The problem is in the following 2 line -

column  = orderCols[k][j];
row     = orderRows[orderCols[k]];

The whole thing could be made easier to read with -

// pertinent declarations

#include <LiquidCrystal.h>

#define k_COL		16
#define k_ROW		 2

char LCDarray[k_ROW][k_COL];

inline void int_swap(int& lhs, int& rhs) {
    int _lhs = lhs; lhs = rhs; rhs = _lhs;
}

int randomWriteArray2(char array[][k_COL])
{
    int orderCols[k_ROW][k_COL];
    int orderRows[k_ROW];
//  randomSeed(time);

    // fill orderCols with "0 to k_COL-1" for all k_ROW
    for ( int j = k_ROW; j--; )
    {
        for ( int k = k_COL; k--; )
        {
            orderCols[j][k] = k;
        }
    }

    // randomize orderCols
    for ( int j = k_ROW; j--; )
    {
        for ( int k = k_COL; k--; )
        {
            int_swap(orderCols[j][k], orderCols[j][random(k_COL)]);
        }
    }

    // fill orderRows with "0 to k_ROW-1"
    for ( int k = k_ROW; k--; )
    {
        orderRows[k] = k;
    }

    // randomize elements
    for ( int k = k_COL; k--; )
    {
        int_swap(orderRows[k], orderRows[random(k_ROW)]);
    }

    // print by randomizing order rows each time and printing all cells in order
    int column, row;                            // extra variables for temporary readability
    for ( int j = 0; j < k_COL; j++ )
    {
        for ( int k = 0; k < k_ROW; k++ )
        {
			column  = orderCols[k][j];
			row     = orderRows[orderCols[k]];
			
			lcd.setCursor(column, row);
			lcd.write(array[row][column]);
			
			delay(100);
        }

        // randomize row pick again
        for ( int k = k_ROW; k--; )
        {
            orderRows[k] = k;
        }

        for ( int k = k_COL; k--; )
        {
            int_swap(orderRows[k], orderRows[random(k_ROW)]);
        }
    }

//    wipeArray(array);

    return 0;
}