Initial commit

2015/puzzle-21-01.cc

@@ -0,0 +1,127 @@
+#include <string>
+#include <vector>
+#include <iostream>
+#include <cstdlib>
+#include <numeric>
+
+using namespace std::string_literals;
+
+struct Item {
+    std::string name_;
+    unsigned long cost_;
+    unsigned long damage_;
+    unsigned long armour_;
+
+    bool operator==(Item const& rhs) const { return name_ == rhs.name_; }
+};
+
+struct Person {
+    Person(unsigned long hp, unsigned long damage, unsigned long armour) : name_("Enemy"), hp_(hp),
+                                                                           cost_(std::numeric_limits<unsigned>::max()),
+                                                                           damage_(damage),
+                                                                           armour_(armour) {}
+
+    Person(Item const &weapon, Item const &armour, Item const &left_ring, Item const &right_ring) :
+            name_("Player: "s + weapon.name_ + ", "s + armour.name_ + ", "s + left_ring.name_ + ", " +
+                  right_ring.name_),
+            hp_(100),
+            cost_(weapon.cost_ + armour.cost_ + left_ring.cost_ + right_ring.cost_),
+            damage_(weapon.damage_ + armour.damage_ + left_ring.damage_ + right_ring.damage_),
+            armour_(weapon.armour_ + armour.armour_ + left_ring.armour_ + right_ring.armour_) {}
+
+    unsigned get_attacked(Person const &attacker) {
+        auto damage{(attacker.damage_ > armour_) ? attacker.damage_ - armour_ : 1};
+        hp_ = (hp_ > damage) ? hp_ - damage : 0;
+        return hp_;
+    }
+
+    std::string name_;
+    unsigned long hp_;
+    unsigned long cost_;
+    unsigned long damage_;
+    unsigned long armour_;
+};
+
+unsigned long get_value(std::string const &begin) {
+    std::string line;
+    if (!std::getline(std::cin, line)) {
+        std::cerr << "Missing line in input\n";
+        std::exit(1);
+    }
+    if (line.substr(0, begin.length()) != begin) {
+        std::cerr << "Line doesn't begin with: " << begin << '\n';
+        std::exit(1);
+    }
+    return std::stoul(line.substr(begin.length()));
+}
+
+bool me_beats_enemy(Person me, Person enemy) {
+    while (true) {
+        enemy.get_attacked(me);
+        if (enemy.hp_ == 0) { return true; }
+        me.get_attacked(enemy);
+        if (me.hp_ == 0) { return false; }
+    }
+}
+
+int main() {
+    const std::string hp_begin{"Hit Points: "};
+    const std::string d_begin{"Damage: "};
+    const std::string a_begin{"Armor: "};
+
+    const std::vector<Item> weapons{
+            {"Dagger",     8,  4, 0},
+            {"Shortsword", 10, 5, 0},
+            {"Warhammer",  25, 6, 0},
+            {"Longsword",  40, 7, 0},
+            {"Greataxe",   74, 8, 0},
+    };
+
+    const std::vector<Item> armours{
+            {"Nothing",    0,   0, 0},
+            {"Leather",    13,  0, 1},
+            {"Chainmail",  31,  0, 2},
+            {"Splintmail", 53,  0, 3},
+            {"Bandedmail", 75,  0, 4},
+            {"Platedmail", 102, 0, 5},
+    };
+
+    const std::vector<Item> rings{
+            {"Empty",      0,   0, 0},
+            {"Damage +1",  25,  1, 0},
+            {"Damage +2",  50,  2, 0},
+            {"Damage +3",  100, 3, 0},
+            {"Defense +1", 20,  0, 1},
+            {"Defense +2", 40,  0, 2},
+            {"Defense +3", 80,  0, 3},
+    };
+
+
+    auto enemy_hp{get_value(hp_begin)};
+    auto enemy_damage{get_value(d_begin)};
+    auto enemy_armour{get_value(a_begin)};
+
+    Person best_result{0, 0, 0};
+    Person enemy{enemy_hp, enemy_damage, enemy_armour};
+
+    for (auto const &weapon: weapons) {
+        if (weapon.cost_ > best_result.cost_) { continue; }
+        for (auto const &armour: armours) {
+            if (weapon.cost_ + armour.cost_ > best_result.cost_) { continue; }
+            for (auto const &left_ring: rings) {
+                if (weapon.cost_ + armour.cost_ + left_ring.cost_ > best_result.cost_) { continue; }
+                for (auto const &right_ring: rings) {
+                    if (weapon.cost_ + armour.cost_ + left_ring.cost_ + right_ring.cost_ >
+                        best_result.cost_) { continue; }
+                    if (left_ring == right_ring) continue;
+                    Person me{weapon, armour, left_ring, right_ring};
+                    if (me_beats_enemy(me, enemy) && me.cost_ < best_result.cost_) {
+                        best_result = me;
+                    }
+                }
+            }
+        }
+    }
+
+    std::cout << "Best person: " << best_result.name_ << " at cost of " << best_result.cost_ << '\n';
+}