Compilare: main.cpp: In function 'int main()': main.cpp:24:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d", &n); ^ main.cpp:26:26: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&x); ^ main.cpp:15:35: warning: iteration 100004 invokes undefined behavior [-Waggressive-loop-optimizations] for ( i=1;i<=nmax;i++) phi[i]=i - 1; ~~~~~~^~~~~~ main.cpp:15:17: note: within this loop for ( i=1;i<=nmax;i++) phi[i]=i - 1; ^