Compilare: user.cpp: In function ‘int main()’: user.cpp:12:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(fscanf(fin, "%d", &t); t; t--){ ^ user.cpp:13:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &n, &p); ^ user.cpp:38:23: warning: ‘u’ may be used uninitialized in this function [-Wmaybe-uninitialized] u=r[u]; ^