Compilare: main.cpp: In function 'void matrice(int, int, int, int)': main.cpp:32:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 32 | while(p < s.size() && isdigit(s[p])) | ~~^~~~~~~~~~ main.cpp:36:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 36 | if (p < s.size() && isalpha(s[p])) | ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:53:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 53 | for (int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:68:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 68 | while (i < s.size() && isdigit(s[i])) | ~~^~~~~~~~~~