Compilare: user.cpp: In function ‘void create_buckets()’: user.cpp:20:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < n; i++){ ^ user.cpp: In function ‘void counting_sort(int)’: user.cpp:29:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < n; i++) ^ user.cpp:41:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < n; i++) ^ user.cpp: In function ‘int main()’: user.cpp:61:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < n; i += 10){ ^ user.cpp:52:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.in","r",stdin); ^ user.cpp:53:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("radixsort.out","w",stdout); ^ user.cpp:54:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&a,&b,&c); ^