Compilare: user.cpp: In function ‘void v1()’: user.cpp:32:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0; k<strlen(sir[i]); k++) ^ user.cpp:34:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0; k<strlen(sir[j]); k++) ^ user.cpp: In function ‘void v2()’: user.cpp:63:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0; k<strlen(sir[i]); k++) ^ user.cpp:65:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0; k<strlen(sir[j]); k++) ^