Compilare: main.cpp: In function 'int main()': main.cpp:25:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(!stiva.empty() && l - i > m - stiva.size() && stiva.top() < s[i] - '0') ~~~~~~^~~~~~~~~~~~~~~~~~ main.cpp:29:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(l - i == m - stiva.size()) ~~~~~~^~~~~~~~~~~~~~~~~~~ main.cpp:24:13: warning: unused variable 'lemq' [-Wunused-variable] int lemq = stiva.size(); ^~~~