2.2. Reading an array.   

In reading data into an array we must systematically access each of the elements of the array. And we must specify them in the order in which the data items themselves are organised. This will be in columns and, as well, usually in rows. Therefore in english: 


      for each row i do

          input all the values in row i

To read in all the values in row i we must consider each of the column positions in the row. Therefore 

      for each row i do        /* read the array A */

          for each column j do

              input a[i,j]

More formally, in pseudo code, we would have: 

      for i  1 to n do

          for j  1 to n do

              input a[i,j]

          endfor

      endfor

or using better variable names: 

      for row  1 to n do

          for column  1 to n do

              input a[row,column]

          endfor

      endfor