Compilare: user.cpp: In function ‘int main()’: user.cpp:23:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= sir1.length(); ++i) ^ user.cpp:24:49: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 1; j <= sir2.length(); ++j) { ^ user.cpp:31:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 1; j <= sir2.length(); ++j) { ^ user.cpp:12:12: warning: unused variable ‘n’ [-Wunused-variable] int t, n; ^