问答题

本题中数组arr中存储了学生的成绩,分别为87,45,56,78,67,56,91,62,82,63,程序的功能是计算低于平均分的人数,并打印输出结果。请在程序空缺部分填写适当内容,使程序能正确运行。
public class java1
public static void main(String[]args)
int arr[]=56,91,78,67,56,87,45,62,82,63);
int num=art.length;
int i=0;
int sumScore=0;
int sumNum=0;
double average;
while(i<num)
sumScore=sumScore+arr[i];
______;
average=______;
i=0;
do
if(arr[i]<average)
sumNum++;
i++;
while(______);
System.out.println("average:"+average+",belows average:"+sumNum);

【参考答案】

第1处:i++或i=i+1或i+=1
第2处:(double)sumScore/num
第3处:i<hum
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