Compilare: main.cpp: In function 'int get_number_at(int&)': main.cpp:40:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(; cursor<to_solve.length()&&is_digit(to_solve[cursor]); cursor++) ~~~~~~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int get_numbers()': main.cpp:49:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(; c<to_solve.length(); c++) ~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int get_sum(std::vector<int>&)': main.cpp:69:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<vec.size(); i++) ~^~~~~~~~~~~ main.cpp: In function 'int get_max_sum(std::vector<int>&)': main.cpp:79:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<vec.size(); i++) ~^~~~~~~~~~~ main.cpp: In function 'int solve(int&, int)': main.cpp:127:1: warning: control reaches end of non-void function [-Wreturn-type] } ^