Compilare: user.cpp: In function ‘int main()’: user.cpp:9:15: warning: unused variable ‘ok’ [-Wunused-variable] int K,i,n,ok,k,x,j; ^ user.cpp:9:18: warning: unused variable ‘k’ [-Wunused-variable] int K,i,n,ok,k,x,j; ^ user.cpp:10:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&K); ^ user.cpp:25:23: warning: ‘x’ may be used uninitialized in this function [-Wmaybe-uninitialized] fprintf(g,"%d",x*x); ^