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  1. #include <cassert>
  2. #include <cstddef>
  3. #include <bitset>
  4.  
  5. using weapon_id = unsigned long long;
  6.  
  7. // Available weapons - reduced for brevity
  8. // Ideally, adding a new weapon here wouldn't require editing anything below.
  9. static const weapon_id WEAPON_HARSH_LANGUAGE = 0;
  10. static const weapon_id WEAPON_SHARP_STICK =    1;
  11. static const weapon_id WEAPON_KNIFE =          2;
  12. static const weapon_id WEAPON_NUKE =           3;
  13. static const std::size_t WEAPON_COUNT =        4; // Could potentially be > 64
  14.  
  15. using weapon_set = std::bitset< WEAPON_COUNT >;
  16.  
  17.  
  18. // Select the next available weapon.
  19. // If only one weapon is available, return that weapon.
  20. // If the last weapon is currently selected then cycle back around to the first.
  21. weapon_id next_weapon(const weapon_set& weapons, const weapon_id current_weapon)
  22. {
  23. 	assert(weapons.any());
  24.  
  25. 	if (weapons.count() == 1)
  26. 	{
  27. 		return current_weapon;
  28. 	}
  29.  
  30. 	auto new_weapon = current_weapon;
  31. 	// Insert magic here.
  32. 	return new_weapon;
  33. }
  34.  
  35.  
  36. // Select the previous available weapon.
  37. // If only one weapon is available, return that weapon.
  38. // If the first weapon is currently selected then cycle back around to the last.
  39. weapon_id prev_weapon(const weapon_set& weapons, const weapon_id current_weapon)
  40. {
  41. 	assert(weapons.any());
  42.  
  43. 	if (weapons.count() == 1)
  44. 	{
  45. 		return current_weapon;
  46. 	}
  47.  
  48. 	auto new_weapon = current_weapon;
  49. 	// Insert magic here
  50. 	return new_weapon;
  51. }
  52.  
  53. // Test cases I can think of. Have I missed any?
  54. int main()
  55. {
  56. 	// Test 1 - One weapon
  57. 	{
  58. 		weapon_set weapons;
  59. 		weapons.set(WEAPON_HARSH_LANGUAGE);
  60. 		assert(next_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_HARSH_LANGUAGE);
  61. 		assert(prev_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_HARSH_LANGUAGE);
  62. 	}
  63.  
  64. 	// Test 2 - Two 'sequential' weapons
  65. 	{
  66. 		weapon_set weapons;
  67. 		weapons.set(WEAPON_SHARP_STICK);
  68. 		weapons.set(WEAPON_KNIFE);
  69. 		assert(next_weapon(weapons, WEAPON_SHARP_STICK) == WEAPON_KNIFE);
  70. 		assert(prev_weapon(weapons, WEAPON_SHARP_STICK) == WEAPON_KNIFE);
  71. 		assert(next_weapon(weapons, WEAPON_KNIFE) == WEAPON_SHARP_STICK);
  72. 		assert(prev_weapon(weapons, WEAPON_KNIFE) == WEAPON_SHARP_STICK);
  73. 	}
  74.  
  75. 	// Test 3 - Two 'non sequential' weapons
  76. 	{
  77. 		weapon_set weapons;
  78. 		weapons.set(WEAPON_HARSH_LANGUAGE);
  79. 		weapons.set(WEAPON_KNIFE);
  80. 		assert(next_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_KNIFE);
  81. 		assert(prev_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_KNIFE);
  82. 		assert(next_weapon(weapons, WEAPON_KNIFE) == WEAPON_HARSH_LANGUAGE);
  83. 		assert(prev_weapon(weapons, WEAPON_KNIFE) == WEAPON_HARSH_LANGUAGE);
  84. 	}
  85.  
  86. 	// Test 4 - All weapons
  87. 	{
  88. 		weapon_set weapons;
  89. 		weapons.set(WEAPON_HARSH_LANGUAGE);
  90. 		weapons.set(WEAPON_SHARP_STICK);
  91. 		weapons.set(WEAPON_KNIFE);
  92. 		weapons.set(WEAPON_NUKE);
  93. 		assert(next_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_SHARP_STICK);
  94. 		assert(prev_weapon(weapons, WEAPON_HARSH_LANGUAGE) == WEAPON_NUKE);
  95. 		assert(next_weapon(weapons, WEAPON_NUKE) == WEAPON_HARSH_LANGUAGE);
  96. 		assert(prev_weapon(weapons, WEAPON_NUKE) == WEAPON_KNIFE);
  97. 	}
  98.  
  99. 	return 0;
  100. }
Runtime error #stdin #stdout #stderr 0s 3472KB
comments (?)
stdin 
Standard input is empty
stdout 
Standard output is empty
stderr 
prog: prog.cpp:69: int main(): Assertion `next_weapon(weapons, WEAPON_SHARP_STICK) == WEAPON_KNIFE' failed.
https://ideone.com/nRIZVm
language:
C++14 (gcc 8.3)
created:
11 years ago
visibility:
public

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