Compilare: main.cpp: In function 'int main()': main.cpp:25:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 25 | for(int i = 0; i < s.size(); i++){ | ~~^~~~~~~~~~ main.cpp:26:18: warning: array subscript has type 'char' [-Wchar-subscripts] 26 | frec[s[i]] = i + 1; | ^ main.cpp:42:30: warning: array subscript has type 'char' [-Wchar-subscripts] 42 | if(frec[matr[i][j]]){ | ~~~~~~~~~^ main.cpp:43:45: warning: array subscript has type 'char' [-Wchar-subscripts] 43 | q.push({i, j, frec[matr[i][j]], frec[matr[i][j]]}); | ~~~~~~~~~^ main.cpp:43:63: warning: array subscript has type 'char' [-Wchar-subscripts] 43 | q.push({i, j, frec[matr[i][j]], frec[matr[i][j]]}); | ~~~~~~~~~^ main.cpp:44:40: warning: array subscript has type 'char' [-Wchar-subscripts] 44 | dp[i][j][frec[matr[i][j]]][frec[matr[i][j]]] = 0; | ~~~~~~~~~^ main.cpp:44:58: warning: array subscript has type 'char' [-Wchar-subscripts] 44 | dp[i][j][frec[matr[i][j]]][frec[matr[i][j]]] = 0; | ~~~~~~~~~^