Compilare: user.cpp: In function ‘void rad_sort()’: user.cpp:36:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<q[i].size();j++) ^ user.cpp: In function ‘void read()’: user.cpp:14:37: 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); ^ user.cpp: In function ‘int main()’: user.cpp:46:38: 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:47:40: 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); ^