Compilare: main.cpp: In function 'int main()': main.cpp:11:22: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ main.cpp:20:26: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&x); ^ main.cpp:16:13: warning: iteration 99999 invokes undefined behavior [-Waggressive-loop-optimizations] if (phi[i]==i) ~~~~~^ main.cpp:15:12: note: within this loop for ( i=2;i<=nmax;i++) ^ main.cpp:13:35: warning: iteration 100000 invokes undefined behavior [-Waggressive-loop-optimizations] for ( i=1;i<=nmax;i++) phi[i]=i; ~~~~~~^~ main.cpp:13:17: note: within this loop for ( i=1;i<=nmax;i++) phi[i]=i; ^