Data update

Task/Knapsack-problem-Unbounded/C++/knapsack-problem-unbounded.cpp

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+#include <algorithm>
+#include <cmath>
+#include <cstdint>
+#include <iomanip>
+#include <iostream>
+#include <string>
+#include <vector>
+
+struct Item {
+	std::string name;
+	int32_t value;
+	double weight;
+	double volume;
+};
+
+const std::vector<Item> items = {
+	Item("panacea", 3000, 0.3, 0.025),
+	Item("ichor", 1800, 0.2, 0.015),
+	Item("gold", 2500, 2.0, 0.002)
+};
+constexpr double MAX_WEIGHT = 25.0;
+constexpr double MAX_VOLUME = 0.25;
+
+std::vector<int32_t> count(items.size(), 0);
+std::vector<int32_t> best(items.size(), 0);
+int32_t best_value = 0;
+
+void knapsack(const uint64_t& i, const int32_t& value, const double& weight, const double& volume) {
+    if ( i == items.size() ) {
+        if ( value > best_value ) {
+            best_value = value;
+            best = count;
+        }
+        return;
+    }
+
+    int32_t measure1 = (int32_t) std::floor( weight / items[i].weight );
+    int32_t measure2 = (int32_t) std::floor( volume / items[i].volume );
+    int32_t measure  = std::min(measure1, measure2);
+    count[i] = measure;
+
+    while ( count[i] >= 0 ) {
+        knapsack(
+            i + 1,
+            value  + count[i] * items[i].value,
+            weight - count[i] * items[i].weight,
+            volume - count[i] * items[i].volume
+        );
+        count[i]--;
+    }
+}
+
+int main() {
+	knapsack(0, 0, MAX_WEIGHT, MAX_VOLUME);
+	std::cout << "Item Chosen  Number Value  Weight  Volume" << std::endl;
+	std::cout << "-----------  ------ -----  ------  ------" << std::endl;
+	int32_t item_count = 0;
+	int32_t number_sum = 0;
+	double weight_sum = 0.0;
+	double volume_sum = 0.0;
+	
+	for ( uint64_t i = 0; i < items.size(); ++i ) {
+		if ( best[i] == 0 ) {
+			continue;
+		}
+		
+		item_count++;
+		std::string name = items[i].name;
+		int32_t number = best[i];
+		int32_t value = items[i].value * number;
+		double weight = items[i].weight * number;
+		double volume = items[i].volume * number;
+		number_sum += number;
+		weight_sum += weight;
+		volume_sum += volume;
+		
+		std::cout << std::setw(11) << name << std::setw(6) << number << std::setw(8) << value << std::fixed
+				  << std::setw(8) << std::setprecision(2) << weight
+				  << std::setw(8) << std::setprecision(2) << volume << std::endl;
+	}
+	
+	std::cout << "-----------  ------ -----  ------  ------" << std::endl;
+	std::cout << std::setw(5) << item_count << " items" << std::setw(6) << number_sum << std::setw(8) << best_value
+			  << std::setw(8) << weight_sum << std::setw(8) << volume_sum << std::endl;
+}