B2: checker_board

Problem

Print the pattern:

#O#O
O#O#
#O#O
O#O#
#O#O
O#O#
#O#O
O#O#

51. B2: checker_board, Comet 64

Solution 1

Use a string of x and o to encode the pattern.

x := true
o := false

The register int is used as an index i to each string character. Check whether character at index i is x and print the boolean result.

str = xoxooxoxxoxooxoxxoxooxoxxoxooxox;  // Encoded pattern.
char = str[int];  // Character at index i.
check char = x;   // Is character = x?
output = bool;    // Print boolean result.
int++;            // Increment index.

Solution 2

Consider the pattern

x o x o
o x o x

This pattern is repeated 4 times. We need to print the above pattern 4 times. This solution is optimal, according to the game.

output = true;   // The pattern xoxo.
output = false;  //
output = true;   //
output = false;  //
output = false;  // The pattern oxox.
output = true;   //
output = false;  //
output = true;   //