统计专业人数.c

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

struct ListNode {
char code[8];
struct ListNode *next;
};

struct ListNode *createlist(); /*裁判实现，细节不表*/
int countcs( struct ListNode *head );

int main()
{
struct ListNode *head;

head = createlist();
printf("%d\n", countcs(head));

return 0;
}
struct ListNode *createlist()
{
struct ListNode *head = NULL, *tail = NULL;
char code[8];

scanf("%s", code);
while (code[0] != '#') {
struct ListNode *p = (struct ListNode *)malloc(sizeof(struct ListNode));
strcpy(p->code, code);
p->next = NULL;

if (head == NULL) {
head = p;
} else {
tail->next = p;
}
tail = p;

scanf("%s", code);
}

return head;
}
int countcs(struct ListNode *head)
{
int count = 0;
struct ListNode *p;
p=head;
while (p != NULL) {
if (p->code[1] == '0' && p->code[2] == '2')
count++;
p = p->next;
}
return count;
}