/in/foo.cc: In member function 'void BigInt::mul(int)':
/in/foo.cc:17:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |         for(int i=0;i<digits.size();i++){
      |                     ~^~~~~~~~~~~~~~
/in/foo.cc: In member function 'BigInt BigInt::operator*(const BigInt&)':
/in/foo.cc:34:23: 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<digits.size();i++){
      |                      ~^~~~~~~~~~~~~~
/in/foo.cc:35:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |             for (int j=0;j<other.digits.size();j++) {
      |                          ~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:39:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for (int i=0;i<result.digits.size();i++) {
      |                  ~^~~~~~~~~~~~~~~~~~~~~
/in/foo.cc:41:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |             if (i+1==result.digits.size()) {
      |                 ~~~^~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc: In member function 'BigInt BigInt::operator+(const BigInt&)':
/in/foo.cc:74:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |         while (i<digits.size()||i<other.digits.size()||carry) {
      |                ~^~~~~~~~~~~~~~
/in/foo.cc:74:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |         while (i<digits.size()||i<other.digits.size()||carry) {
      |                                 ~^~~~~~~~~~~~~~~~~~~~
/in/foo.cc:76:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |             if(i<digits.size()) sum+=digits[i];
      |                ~^~~~~~~~~~~~~~
/in/foo.cc:77:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |             if(i<other.digits.size()) sum+=other.digits[i];
      |                ~^~~~~~~~~~~~~~~~~~~~