Compilare: user.c: In function ‘prim’: user.c:8:16: warning: implicit declaration of function ‘sqrt’ [-Wimplicit-function-declaration] for(i=2;i<=sqrt(a);i++) ^ user.c:8:16: warning: incompatible implicit declaration of built-in function ‘sqrt’ user.c:8:16: note: include ‘<math.h>’ or provide a declaration of ‘sqrt’ user.c: In function ‘main’: user.c:33:31: warning: implicit declaration of function ‘pow’ [-Wimplicit-function-declaration] fi*=(i-1)*pow(i,w-1); ^ user.c:33:31: warning: incompatible implicit declaration of built-in function ‘pow’ user.c:33:31: note: include ‘<math.h>’ or provide a declaration of ‘pow’ user.c:15:30: warning: unused variable ‘pw’ [-Wunused-variable] int i,m,w=0,k=0,p[10000],pw[10000],n,fi,nr=0,j; ^ user.c:15:21: warning: unused variable ‘p’ [-Wunused-variable] int i,m,w=0,k=0,p[10000],pw[10000],n,fi,nr=0,j; ^ user.c:15:17: warning: variable ‘k’ set but not used [-Wunused-but-set-variable] int i,m,w=0,k=0,p[10000],pw[10000],n,fi,nr=0,j; ^ user.c:18:5: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^