Compilare: main.cpp: In function 'int main()': main.cpp:17:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=1;i<s.size();i++) d[i]=s[i]-'0'+d[i-1]; ~^~~~~~~~~ main.cpp:20:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=k;i<s.size();i++) ~^~~~~~~~~