#include <stdio.h>

int main() {

  int num_cols = 6;
  int num_rows = 4;
  int col_i, row_i;
  int matrix[ num_rows ][ num_cols ];

  for ( row_i = 0; row_i < num_rows; row_i++ ) {
    for ( col_i = 0; col_i < num_cols; col_i++) {
      matrix[ row_i ][ col_i ] = ( row_i + 1 ) * ( col_i + 1 );
    }
  }

  printf( "\n" );

  printf( "The Matrix is (w no loops): \n" );
  printf( " %2d %2d %2d %2d %2d %2d\n", matrix[0][0], matrix[0][1], matrix[0][2], matrix[0][3], matrix[0][4], matrix[0][5] );
  printf( " %2d %2d %2d %2d %2d %2d\n", matrix[1][0], matrix[1][1], matrix[1][2], matrix[1][3], matrix[1][4], matrix[1][5] );
  printf( " %2d %2d %2d %2d %2d %2d\n", matrix[2][0], matrix[2][1], matrix[2][2], matrix[2][3], matrix[2][4], matrix[2][5] );
  printf( " %2d %2d %2d %2d %2d %2d\n", matrix[3][0], matrix[3][1], matrix[3][2], matrix[3][3], matrix[3][4], matrix[3][5] );
  printf( "\n" );

  printf( "The Matrix is (w one loop): \n" );
  for ( row_i = 0; row_i < num_rows; row_i++ ) {
    printf( " %2d %2d %2d %2d %2d %2d\n", matrix[ row_i ][0], matrix[ row_i ][1], matrix[ row_i ][2], matrix[ row_i ][3], matrix[ row_i ][4], matrix[ row_i ][5] );
  }
  printf( "\n" );

  printf( "The Matrix is (w nested loops): \n" );
  for ( row_i = 0; row_i < num_rows; row_i++ ) {
    for ( col_i = 0; col_i < num_cols; col_i++ ) {
      printf( " %2d", matrix[ row_i ][ col_i ] );
    }
    printf( "\n" );
  }

  printf( "\n" );
  return 0;
}