Compilare: user.c: In function ‘main’: user.c:41:29: warning: unused variable ‘retin’ [-Wunused-variable] int e = 0, sum = 0, retin = n,ans1 = 1, ans2 = 1; ^ user.c:41:20: warning: unused variable ‘sum’ [-Wunused-variable] int e = 0, sum = 0, retin = n,ans1 = 1, ans2 = 1; ^ user.c:41:13: warning: unused variable ‘e’ [-Wunused-variable] int e = 0, sum = 0, retin = n,ans1 = 1, ans2 = 1; ^ user.c:36:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssnd.in","r",stdin); ^ user.c:37:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssnd.out","w",stdout); ^ user.c:38:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ user.c:40:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^