Compilare: user.cpp: In function ‘int main()’: user.cpp:47:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&n,&q); ^ user.cpp:51:23: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&v[i]); ^ user.cpp:55:48: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&queries[i].l,&queries[i].r); ^ user.cpp:94:23: warning: ‘best’ may be used uninitialized in this function [-Wmaybe-uninitialized] ans[queries[i].id] = best; ~~~~~~~~~~~~~~~~~~~^~~~~~ user.cpp:71:17: warning: ‘dr’ may be used uninitialized in this function [-Wmaybe-uninitialized] fr[v[++dr]]++; ^