Compilare: user.cpp: In function ‘int main()’: user.cpp:34:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1; (((i*i)<<1)+(i<<1))<=x; ++i) ^ user.cpp:38:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=(((i*i)<<1)+(i<<1)) ; (j<<1) <=x; j+= (i<<1) +1 ) ^ user.cpp:47:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=n;i++) ^ user.cpp:52:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( j=0; j<m && prim[j]<mx; ++j) ^ user.cpp:46:10: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fs(n); ^ user.cpp:49:14: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fs(x); ^