随机产生30个学生的C语言成绩(成绩范围在[0，100]之间)，统计并输出不及格(<60分)的人数，并按照从大到小的顺序将数组所有元素进行排序，分别显示排序前和排序后的结果，每行输出10个。

好的，我可以帮您解决这个问题。以下是代码：

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define NUM_STUDENTS 30
#define MIN_SCORE 0
#define MAX_SCORE 100
#define PASS_SCORE 60

void print_array(int arr[], int size) {
    for (int i = 0; i < size; i++) {
        printf("%d ", arr[i]);
        if ((i + 1) % 10 == 0) {
            printf("\n");
        }
    }
    printf("\n");
}

int main() {
    int scores[NUM_STUDENTS];
    int num_fail = 0;

    srand(time(NULL));
    for (int i = 0; i < NUM_STUDENTS; i++) {
        scores[i] = rand() % (MAX_SCORE - MIN_SCORE + 1) + MIN_SCORE;
        if (scores[i] < PASS_SCORE) {
            num_fail++;
        }
    }

    printf("Number of students who failed: %d\n", num_fail);

    printf("Scores before sorting:\n");
    print_array(scores, NUM_STUDENTS);

    // Bubble sort
    for (int i = 0; i < NUM_STUDENTS - 1; i++) {
        for (int j = 0; j < NUM_STUDENTS - i - 1; j++) {
            if (scores[j] < scores[j + 1]) {
                int temp = scores[j];
                scores[j] = scores[j + 1];
                scores[j + 1] = temp;
            }
        }
    }

    printf("Scores after sorting:\n");
    print_array(scores, NUM_STUDENTS);

    return 0;
}

希望这个代码可以帮到您！