Added older advents

advent_of_code_2015/day6/main2.cc

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+#include "main.ih"
+
+int main()
+{
+    vector<Instruction> instructions;
+
+    while(!cin.eof())
+    {
+        Instruction instr;
+        cin >> instr;
+
+        instructions.push_back(instr);
+        cout << "Instruction set " << instr.action << "\n";
+        cout << "    from: [" << instr.from.x << ", " << instr.from.y << "]\n";
+        cout << "    througn: [" << instr.through.x << ", " << instr.through.y << "]\n";
+    }
+
+    vector<vector<int>> lights;
+    lights.resize(1000, vector<int>(1000, 0));
+
+    for (Instruction const &instr : instructions)
+    {
+        for (size_t idx = instr.from.x; idx <= instr.through.x; ++idx)
+        {
+            for (size_t idy = instr.from.y; idy <= instr.through.y; ++idy)
+            {
+                switch(instr.action)
+                {
+                    case TURN_OFF:
+                        lights[idx][idy] 
+                            = lights[idx][idy] ? lights[idx][idy] - 1 : 0;
+                    break;
+
+                    case TURN_ON:
+                        lights[idx][idy] += 1;
+                    break;
+
+                    case TOGGLE:
+                        lights[idx][idy] += 2;
+                    break;
+                }
+            }
+        }
+    }
+
+    size_t brightness = 0;
+    for (size_t idx = 0; idx != lights.size(); ++idx)
+    {
+        for (size_t idy = 0; idy != lights[idx].size(); ++idy)
+            brightness += lights[idx][idy];
+    }
+
+    cout << "Total brightness: " << brightness << "\n";
+}