Compilare: user.cpp: In function ‘int main()’: user.cpp:28:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i<s.length()) ^ user.cpp:31:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (s[i]>='a' && s[i]<='z' && i<s.length()) ^ user.cpp:39:57: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (s[i]>='0' && s[i]<='9' && i<s.length()) ^ user.cpp:52:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<s.size() ;++i) ^ user.cpp:57:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (s[j]>='0' && s[j]<='9' && j<s.length()) ^ user.cpp:66:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<a.size(); ++i) ^ user.cpp:71:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j<a.size() && a[j].first==s1) ^ user.cpp:21:9: warning: unused variable ‘poz1’ [-Wunused-variable] int poz1,poz2; ^ user.cpp:21:14: warning: unused variable ‘poz2’ [-Wunused-variable] int poz1,poz2; ^ user.cpp:24:10: warning: unused variable ‘ok1’ [-Wunused-variable] bool ok1=false; ^