Compilare: user.c: In function ‘main’: user.c:22:5: warning: format ‘%s’ expects argument of type ‘char *’, but argument 2 has type ‘char (*)[1001]’ [-Wformat=] scanf("%s",&s); ^ user.c:29:5: warning: statement with no effect [-Wunused-value] for(i; i>=0;i--) ^ user.c:24:13: warning: unused variable ‘j’ [-Wunused-variable] int i , j; ^ user.c:20:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen(in, "r", stdin); ^ user.c:21:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen(out, "w", stdout); ^ user.c:22:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",&s); ^