Support printout to custom streams

board.cc

@@ -61,15 +61,15 @@ int Board::at(const int row, const int column) const {
   return board_[row][column];
 }
 
-void Board::print() const {
+void Board::print(std::ostream &ostream) const {
   // Define how many digits are required, at max, to print each value in this board.
   const int value_width = std::floor(std::log10(size_)) + 1;
 
   for (int row = 0; row < size_; ++row) {
     for (int column = 0; column < size_; ++column) {
-      std::cout << std::setw(value_width) << board_[row][column] << " ";
+      ostream << std::setw(value_width) << board_[row][column] << " ";
     }
-    std::cout << std::endl;
+    ostream << std::endl;
   }
 }
 

board.h

@@ -19,7 +19,9 @@
 #ifndef BOARD_H
 #define BOARD_H
 
+#include <iostream>
 #include <vector>
+
 #include "board_iterators.h"
 
 // Defines various ways to initialize a new board.
@@ -65,8 +67,8 @@ class Board {
   // is invalid, returns false.
   bool is_column_valid(const int column) const;
 
-  // Prints the board to standard output.
-  void print() const;
+  // Prints the board to the provided output stream.
+  void print(std::ostream &ostream) const;
 
   // Swaps two rows by index, if both indices are valid, and returns
   // true. Otherwise, does nothing and returns false.

create.cc

@@ -19,17 +19,31 @@
 #include "create.h"
 
 #include <cstdlib>
+#include <fstream>
 
 #include "board.h"
 #include "options.h"
 #include "puzzle.h"
 
 int CreateBoard(const ProgramOptions& options) {
-  Board b{5, BoardInitializer::DIAGONAL_INCREASING};
-  b.print();
+  // Create a board.
+  Board b{options.board_size, BoardInitializer::DIAGONAL_INCREASING};
 
+  // Shuffle randomly based on options
+  // FIXME
+
+  // Print board to the desired location.
+  {
+    std::ofstream out{options.board_output_file, std::ios::out};
+    b.print(out);
+  }
+
+  // Genearte puzzle and print to the desired location.
   Puzzle p{b};
-  p.print();
+  {
+    std::ofstream out{options.puzzle_output_file, std::ios::out};
+    p.print(out);
+  }
 
   return EXIT_SUCCESS;
 }

puzzle.cc

@@ -70,25 +70,25 @@ Puzzle::Puzzle(const Board& board) : Puzzle(board.size()) {
   }
 }
 
-void Puzzle::print() const {
+void Puzzle::print(std::ostream &ostream) const {
   // Define how many digits are required, at max, to print each value in this puzzle.
   const int value_width = std::floor(std::log10(size_)) + 1;
 
-  std::cout << std::setw(value_width) << " ";
+  ostream << std::setw(value_width) << " ";
   for (const int v: top_) {
-    std::cout << std::setw(value_width) << v << " ";
+    ostream << std::setw(value_width) << v << " ";
   }
-  std::cout << std::endl;
+  ostream << std::endl;
 
   for (int row = 0; row < size_; ++row) {
-    std::cout << std::setw(value_width) << left_[row]
-              << std::setw((value_width + 1) * size_ - 1) << ""
-              << std::setw(value_width) << right_[row] << std::endl;
+    ostream << std::setw(value_width) << left_[row]
+            << std::setw((value_width + 1) * size_ - 1) << ""
+            << std::setw(value_width) << right_[row] << std::endl;
   }
 
-  std::cout << std::setw(value_width) << " ";
+  ostream << std::setw(value_width) << " ";
   for (const int v: bottom_) {
-    std::cout << std::setw(value_width) << v << " ";
+    ostream << std::setw(value_width) << v << " ";
   }
-  std::cout << std::endl;
+  ostream << std::endl;
 }

puzzle.h

@@ -19,6 +19,8 @@
 #ifndef PUZZLE_H
 #define PUZZLE_H
 
+#include <iostream>
+
 #include "board.h"
 
 class Puzzle {
@@ -29,8 +31,8 @@ class Puzzle {
   // Creates a puzzle based on an existing, solved board.
   explicit Puzzle(const Board& board);
 
-  // Prints the puzzle to standard output.
-  void print() const;
+  // Prints the puzzle to the provided output stream.
+  void print(std::ostream &ostream) const;
 
 private:
   const int size_;