foo.cc: In constructor 'Bi::Bi(ll)':
foo.cc:27:23: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   27 |                 if (f = a < 0) a = -a;
      |                     ~~^~~~~~~
foo.cc: In member function 'void Bi::input()':
foo.cc:49:42: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |                         for (ll i = 1; i < v.size(); ++i)
      |                                        ~~^~~~~~~~~~
foo.cc: In member function 'Bi Bi::operator+(const Bi&) const':
foo.cc:97:31: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |                         if (i < v.size()) an.v[i] += v[i];
      |                             ~~^~~~~~~~~~
foo.cc:98:31: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   98 |                         if (i < b.v.size()) an.v[i] += b.v[i];
      |                             ~~^~~~~~~~~~~~
foo.cc: In member function 'Bi Bi::operator-(const Bi&) const':
foo.cc:112:31: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |                         if (i < b.v.size()) an.v[i] -= b.v[i];
      |                             ~~^~~~~~~~~~~~
foo.cc: In member function 'Bi Bi::operator*(const Bi&) const':
foo.cc:123:34: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  123 |                 for (ll i = 0; i < b.v.size(); ++i) {
      |                                ~~^~~~~~~~~~~~
foo.cc:127:42: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  127 |                         for (ll j = 0; j < v.size(); ++j) {
      |                                        ~~^~~~~~~~~~
foo.cc: In member function 'Bi Bi::operator*(const int&) const':
foo.cc:143:34: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  143 |                 for (ll j = 0; j < v.size(); ++j) {
      |                                ~~^~~~~~~~~~
foo.cc: In member function 'Bi Bi::operator/(const Bi&) const':
foo.cc:164:41: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  164 |                                 mid = l + r >> 1;
      |                                       ~~^~~
foo.cc: In member function 'Bi Bi::operator%(const Bi&) const':
foo.cc:186:41: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  186 |                                 mid = l + r >> 1;
      |                                       ~~^~~
foo.cc: In member function 'bool Bi::operator==(const Bi&) const':
foo.cc:233:34: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<short int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  233 |                 for (ll i = 0; i < v.size(); ++i)
      |                                ~~^~~~~~~~~~

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