Compilare: main.cpp: In function 'void frequency(std::string&, int&, int*)': main.cpp:11:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 11 | for(i = 1; i <= s.size() ; i++){ | ~~^~~~~~~~~~~ main.cpp:15:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 15 | for(j = 1; j <= s.size(); j++){ | ~~^~~~~~~~~~~ main.cpp: In function 'int getdifferent(int, int*, int*)': main.cpp:26:12: warning: unused variable 'j' [-Wunused-variable] 26 | int i, j, k = 0; | ^ main.cpp: In function 'int main()': main.cpp:35:13: warning: unused variable 'g' [-Wunused-variable] 35 | int h , g, freq1[101], freq2[101], i; | ^ main.cpp:35:40: warning: unused variable 'i' [-Wunused-variable] 35 | int h , g, freq1[101], freq2[101], i; | ^