diff --git a/solver.cpp b/solver.cpp
index 91c0f83..57b19d8 100644
--- a/solver.cpp
+++ b/solver.cpp
@@ -2,7 +2,7 @@
 
 void Solver::generate_set(vector<int> carry) {
 	if(carry.size() == N) {
-		possible.push_back(carry);
+		possible.insert(carry);
 		return;
 	}
 
@@ -21,17 +21,29 @@ vector<int> Solver::guess() {
 	return minimax({}).guess;
 }
 void Solver::learn(vector<int> guess, Response response) {
-	vector<vector<int>> next_possible(0);
+	set<vector<int>> next_possible;
 	for(auto sequence : possible)
 		if(validate(sequence, guess) == response)
-			next_possible.push_back(sequence);
+			next_possible.insert(sequence);
 
 	possible = next_possible;
 }
 
 // TODO
 int Solver::get_weight(vector<int> guess) {
-	return 0;
+	// Indexing by N*somewhere + correct and holding how many sequences got that response
+	vector<int> response_count(N*N+1, 0);
+	for(auto sequence : possible) {
+		Response response = validate(sequence, guess);
+		response_count[N*response.somewhere + response.correct]++;
+	}
+
+	// Get highest possible number of sequences left
+	int max = 0;
+	for(int count : response_count)
+		if(count > max)
+			max = count;
+	return max - possible.count(guess);
 }
 Weighed_guess Solver::minimax(vector<int> carry) {
 	if(carry.size() == N)
@@ -42,7 +54,7 @@ Weighed_guess Solver::minimax(vector<int> carry) {
 		carry.push_back(col);
 
 		Weighed_guess next = minimax(carry);
-		if(next.weight > best.weight)
+		if(best.weight == -1 || next.weight < best.weight)
 			best = next;
 
 		carry.pop_back();
diff --git a/solver.hpp b/solver.hpp
index e050eb9..951ef54 100644
--- a/solver.hpp
+++ b/solver.hpp
@@ -1,6 +1,9 @@
 #pragma once
+#include <set>
 #include "global.hpp"
 
+using std::set;
+
 // For deciding the best guess
 struct Weighed_guess {
 	int weight;
@@ -12,7 +15,7 @@ struct Weighed_guess {
 // Solving the game
 class Solver {
 	int N, M;
-	vector<vector<int>> possible = vector<vector<int>>(0);
+	set<vector<int>> possible;
 public:
 	Solver(int N, int M);