diff --git a/sa.hpp b/sa.hpp
new file mode 100644
index 0000000..bbddade
--- /dev/null
+++ b/sa.hpp
@@ -0,0 +1,60 @@
+#ifndef SIMULATED_ANNEALING_HEADER_12647_H
+#define SIMULATED_ANNEALING_HEADER_12647_H
+
+#include <vector>
+#include <algorithm>
+#include <random>
+
+namespace sa {
+
+class solution {
+	std::vector<long long> items;
+	std::default_random_engine gen;
+	int capacity;
+	int fitness;
+
+	auto calculate_boxes()->int {
+		int count = 0;
+		long long now = 0;
+
+		for (auto i : items) {
+			if (now + i > capacity) {
+				count++;
+				now = i;
+				continue;
+			}
+			now += i;
+		}
+
+		return count;
+	}
+
+	public:
+	solution(const std::vector<long long> &items, int capacity):  // Gera a solução inicial
+		items(items), capacity(capacity), fitness(calculate_boxes()) {
+			std::random_device rdevice;
+			gen.seed(rdevice());
+		}
+
+	solution(const solution &sol): 
+		items(sol.items), gen(sol.gen), capacity(sol.capacity) { // Gera um vizinho da solução
+
+		std::uniform_int_distribution<> dist(0, items.size() - 1);
+		int first = dist(gen);
+		int second = 0;
+		while ((second = dist(gen)) == first) {}
+
+		std::swap(items[first], items[second]);
+		fitness = calculate_boxes();
+	}
+
+	void randomize() {
+		shuffle(items.begin(), items.end(), gen);
+
+		fitness = calculate_boxes();
+	}
+};
+
+} // namespace sa
+
+#endif