程序代码：

#include<stdio.h>
#define N 40
int readscore(int score[]);
int compare(int score[],int i);
int main()
{
    int score[N] ;
    readscore(score);
    printf("学生总数是%d\n",readscore(score));
    compare(score,readscore(score));
    printf("不及格人数是%d",compare(score,readscore(score)));
    return 0;
}
/*函数功能：读取成绩，返回学生人数。*/
int readscore(int score[])
{
    printf("输入学生成绩\n");
    int n=-1;
    do
    {
        n++;
        scanf("%d",&score[n]);
    }while(score[n]>=0);
    return n;
}
/*函数功能：累加不及格的人数。*/
int compare(int score[],int i)
{
    i=0;
    do
    {
        if(score[i]>=0&&score[i]<60)
        i++;
        else
        continue;
    }while(i<=readscore(score));
    return i;
}