有大佬能解释一下这个代码吗？#include<stdio.h>#include<string.h>#include<stdlib.h>struct tongxunlu{ char xingming[11]; char shengri[9]; char dianhuahaoma[18];} s[10];int cmp(void const *a, void const *b){ return strcmp(((struct tongxunlu *)a)->shengri, ((struct tongxunlu *)b)->shengri);}int main(){ int n, i; scanf("%d", &n); for (i = 0; i < n; i++) scanf("%s%s%s", s[i].xingming, s[i].shengri, s[i].dianhuahaoma); qsort(s, n, sizeof(s[0]), cmp); for (i = 0; i < n; i++) printf("%s %s %s\n", s[i].xingming, s[i].shengri, s[i].dianhuahaoma); return 0;}