permutation.cpp: In constructor 'BigInt::BigInt(std::string)':
permutation.cpp:19:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
19 | for (int i=0; i<s.size(); ++i) {
| ~^~~~~~~~~
permutation.cpp: In member function 'const BigInt BigInt::operator+(const BigInt&) const':
permutation.cpp:40:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
40 | for (int i=0; i<digits.size() || i<other.digits.size(); ++i) {
| ~^~~~~~~~~~~~~~
permutation.cpp:40:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
40 | for (int i=0; i<digits.size() || i<other.digits.size(); ++i) {
| ~^~~~~~~~~~~~~~~~~~~~
permutation.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
41 | int x = i < digits.size() ? digits[i] : 0;
| ~~^~~~~~~~~~~~~~~
permutation.cpp:42:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
42 | int y = i < other.digits.size() ? other.digits[i] : 0;
| ~~^~~~~~~~~~~~~~~~~~~~~
permutation.cpp: In member function 'const BigInt BigInt::operator-(const BigInt&) const':
permutation.cpp:58:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
58 | int x = i < digits.size() ? digits[i] : 0;
| ~~^~~~~~~~~~~~~~~
permutation.cpp:59:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
59 | int y = i < other.digits.size() ? other.digits[i] : 0;
| ~~^~~~~~~~~~~~~~~~~~~~~
permutation.cpp:63:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
63 | for (int i=0; i<ret.digits.size(); ++i) {
| ~^~~~~~~~~~~~~~~~~~