Compilare: user.c: In function ‘main’: user.c:50:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, *a; ^ user.c:57:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s%n", s1, &slen); ^ user.c:58:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s2); ^