Compilare: main.cpp: In function 'int main()': main.cpp:12:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ~^~~~~~~~~ main.cpp:17:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=i+1;j<s.size();j++) ~^~~~~~~~~ main.cpp:9:15: warning: unused variable 'n' [-Wunused-variable] long long n=0, nr=0; ^