Compilare: user.c: In function ‘init’: user.c:22:5: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] qsort(poz,poz+N,sizeof(poz[0]),cmp); ^~~~~ user.c: In function ‘read_data’: user.c:8:5: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^~~~~~~~~~~~~~ user.c:10:9: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x[i]); ^~~~~~~~~~~~~~~~~ user.c: In function ‘main’: user.c:71:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv.in","r",stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:72:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv.out","w",stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~