提高篇16-19第二题

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
//第二题
void calcu(int);//处理和分数相关的功能
int main()
{
	int num;        //小组人数
	printf("小组共有多少名同学?");
	scanf("%d", &num);
	if (num >= 50)
	{
		printf("输入人超过50，输入错误");
		exit(0);
	}
	else
		calcu(num);
		return 0;
}
void calcu(int num)//输入num名同学的成绩
{
	double std_dev = 0, ave, temp_sum = 0;//标准差
	int count_max = 0, count_min = 0,sum=0;
	int max_score[50], min_score[50];
	int score[50]; //保存成绩的数组，不会超过50名
	int i,temp_score;
	int max, min;
	printf("请输入学生成绩：\n");
	for (i = 0; i < num; i++)
	{
		printf("请输入第%d名学生的成绩:", i + 1);
		scanf("%d", &temp_score);
		if (temp_score >= 0 && temp_score <= 100)
			score[i] = temp_score;
		else
		{
			printf("分数输入范围错误，请重新输入\n");
			i--;
		}
	}
	max = score[0];
	min = score[0];
	for (i = 0; i < num; i++)
	{
		sum += score[i];
		if (score[i] >= max)
			max = score[i];
		if (score[i] <= min)
			min = score[i];
	}
	ave = sum / num;
	printf("最高成绩为%d,最低成绩为%d,平均成绩为%.1lf\n",max,min,ave);
	for (i = 0; i < num; i++)
	{
		if (score[i] == max)
		{
			max_score[count_max] = i;
			count_max++;
		}
		if (score[i] == min)
		{
			min_score[count_min] = i;
			count_min++;
		}
	}
	printf("取得最高分%d分共%d人,他们的学号是：", max, count_max);
	for (i = 0; i < count_max; i++)
		printf("%d ", max_score[i]+1);
	printf("\n");
	printf("取得最低分%d分共%d人,他们的学号是：", min, count_min);
	for (i = 0; i < count_min; i++)
		printf("%d ", min_score[i]+1);
	printf("\n");
	for (i = 0; i < num; i++)
	{
		temp_sum += (score[i] - ave)*(score[i] - ave);
	}
	temp_sum /= num - 1;
	std_dev = sqrt(temp_sum);
	printf("标准偏差为%.3lf\n", std_dev);
}