Scanner函数无法编译是什么情况?
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import java.util.Scanner; public class Sscanner { public static void main (String args[]){ Scanner reader=new Scanner(System.in); double sum=0; int m=0; while(reader.hasNextDouble()){ double x=reader.nextDouble(); m=m+1; sum=sum+x; } System.out.printf("%d个数的和是%f\n",m,sum); System.out.printf("%d个数的平均值是%f\n",m,sum/m); } }