%求100-1000内的素数,并求所有素数的和及平均值n=0; for m=100:1000 flag=1; j=m-1; i=2; while i<=j & flag if rem(m,i)==0 flag=0; end i=i+1; end if flag n=n+1; prime(n)=m; end end k=find(prime>100&prime<1000);total=sum(prime)average=total/length(k)