Compilare: main.cpp: In function 'int main()': main.cpp:71:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<s.size();j++){ ~^~~~~~~~~ main.cpp:97:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<s.size();j++){ ~^~~~~~~~~ main.cpp:128:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<s.size();j++){ ~^~~~~~~~~ main.cpp:149:6: warning: unused variable 'ans2' [-Wunused-variable] int ans2=0; ^~~~