perm.cpp: In function 'std::vector<int> construct_permutation(long long int)':
perm.cpp:19:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |   for (int i = 0; i < x.size(); i++)x[i]++;
      |                   ~~^~~~~~~~~~
perm.cpp:27:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |   for (int i = 0; i < x.size(); i++)x[i]++;
      |                   ~~^~~~~~~~~~
perm.cpp:34:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |  for (int i = 0; i < x.size(); i++)x[i] += 2;
      |                  ~~^~~~~~~~~~