removing input from git

2020/day_5/binary_boarding.cc

@@ -15,6 +15,11 @@ std::vector<std::string> read_input_file() {
   return data;
 }
 
+template <typename T>
+T peek_back(T it) {
+    return --it;
+}
+
 int parse_id(std::string ticket) {
   std::replace(ticket.begin(), ticket.end(), 'F', '0');
   std::replace(ticket.begin(), ticket.end(), 'L', '0');
@@ -28,8 +33,7 @@ int solve_a(const std::set<int> &ids) { return *ids.rbegin(); }
 
 int solve_b(const std::set<int> &ids) {
   for(auto it = ++ids.begin(); it != ids.end(); it++){
-    auto prev = it; --prev;
-    if(*prev + 2 == *it) return *it - 1;
+    if(*peek_back(it) + 2 == *it) return *it - 1;
   }
   return 0;
 }