Merge branch 'paul' into AL/races-potions

src/position.cc

@@ -43,3 +43,34 @@ size_t find(const std::vector<position> &sorted_list,
 
     return sorted_list.size();
 }
+
+#include <algorithm>
+
+std::vector<position> remove_from_list(const std::vector<position>
+                                       &sorted_positions,
+                                       std::vector<position> excluded) {
+        std::sort(excluded.begin(), excluded.end());
+
+        std::vector<position> result{sorted_positions.size() - excluded.size()};
+
+        auto exc = excluded.begin();
+
+        for (auto src : sorted_positions) {
+                if (exc != excluded.end() && src == *exc)
+                        ++exc;
+                else
+                        result.push_back(src);
+        }
+
+        return result;
+}
+
+void remove_from_list(std::vector<position>
+                      &positions,
+                      position &excluded) {
+        for (auto i = positions.begin(); i != positions.end(); ++i)
+                if (*i == excluded) {
+                        positions.erase(i);
+                        return;
+                }
+}