road.cpp: In function 'void solve()':
road.cpp:82:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |  for(int i = 0; i < vec.sz(); i++){
      |                 ~~^~~~~~~~~~
road.cpp:83:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |   for(int j = i+1; j < vec.sz(); j++){
      |                    ~~^~~~~~~~~~
road.cpp:89:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |    for(int k = 0; k < vec.sz(); k++){
      |                   ~~^~~~~~~~~~
road.cpp: In function 'int main()':
road.cpp:17:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | #define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
      |                                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
road.cpp:108:2: note: in expansion of macro 'file'
  108 |  file("road");
      |  ^~~~
road.cpp:17:77: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | #define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
      |                                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
road.cpp:108:2: note: in expansion of macro 'file'
  108 |  file("road");
      |  ^~~~