#include <stdio.h>
#include <stdlib.h>

#define USE_SUBSCRIPT_NOTATION 1
#define USE_POINTER_NOTATION   0

int test_automatic_matrix()
{
	// Read dimensions. They must be larger than 0
	size_t rows = 0, cols = 0;
	if ( scanf("%zu %zu\n", &rows, &cols) != 2 )
		return 1;
	if ( rows * cols == 0 )
		return 2;

	// Creates the matrix in stack segment: dangerous
	long double values[rows][cols];

	// Read values
	for ( size_t row_index = 0; row_index < rows; ++row_index )
	{
		for ( size_t col_index = 0; col_index < cols; ++col_index )
		{
          #if USE_SUBSCRIPT_NOTATION
			if ( scanf("%Lg", &values[row_index][col_index]) != 1 )
				return 3;
          #endif
          #if USE_POINTER_NOTATION
			if ( scanf("%Lg", *(values + row_index) + col_index) != 1 )
				return 3;
          #endif
		}
	}

	// Print values
	for ( size_t row_index = 0; row_index < rows; ++row_index )
	{
		for ( size_t col_index = 0; col_index < cols; ++col_index )
		{
          #if USE_SUBSCRIPT_NOTATION
			printf("%Lg ", values[row_index][col_index]);
          #endif
          #if USE_POINTER_NOTATION
			printf("%Lg ", *(*(values + row_index) + col_index));
          #endif
		}
		putchar('\n'); // fputc(stdout, '\n');
	}

	// Matrix is automatically deallocated when function call ends
	return 0;
}

int dynamic_allocated_matrix()
{
	// Read dimensions. They must be larger than 0
	size_t rows = 0, cols = 0;
	if ( scanf("%zu %zu\n", &rows, &cols) != 2 )
		return 4;
	if ( rows * cols == 0 )
		return 5;

	// Create array in heap segment (dynamic memory): safer
  #if USE_SUBSCRIPT_NOTATION
	// Request for un-continous memory, i.e an array of arrays
	long double** values = (long double**)malloc(rows * sizeof(long double*));
	if ( values == NULL )
		return 6;

	// We now have a pointer array only
	// We have to create cells to store long double values
	for ( size_t row_index = 0; row_index < rows; ++row_index )
		if ( (values[row_index] = (long double*)malloc(cols * sizeof(long double))) == NULL )
			return 7;
  #endif
  #if USE_POINTER_NOTATION
	// Request for continous memory, i.e a matrix stored as an array
	long double* values = malloc(rows * cols * sizeof(long double));
	if ( values == NULL )
		return 8;
  #endif

	// Read values
	for ( size_t row_index = 0; row_index < rows; ++row_index )
	{
		for ( size_t col_index = 0; col_index < cols; ++col_index )
		{
          #if USE_SUBSCRIPT_NOTATION
			scanf("%Lg", &values[row_index][col_index]);
          #endif
          #if USE_POINTER_NOTATION
			scanf("%Lg", values + row_index * cols + col_index);
          #endif
		}
	}

	for ( size_t row_index = 0; row_index < rows; ++row_index )
	{
		for ( size_t col_index = 0; col_index < cols; ++col_index )
		{
          #if USE_SUBSCRIPT_NOTATION
			printf("%Lg ", values[row_index][col_index]);
          #endif
          #if USE_POINTER_NOTATION
			printf("%Lg ", *(values + row_index * cols + col_index));
          #endif
		}
		putchar('\n'); // fputc(stdout, '\n');
	}

	// Dynamic allocated memory MUST be released by programmer
  #if USE_SUBSCRIPT_NOTATION
	for ( size_t row_index = 0; row_index < rows; ++row_index )
		free(values[row_index]);
	free(values);
  #endif
  #if USE_POINTER_NOTATION
	free(values);
  #endif

	return 0;
}

int main()
{
	int result = 0;
	if ( ( result = test_automatic_matrix() ) != 0 )
		return result;

	putchar('\n');
	return dynamic_allocated_matrix();
}