作业 - 第八周

// 比较等长的列表元素，即可获得合并的元素
// 1. 链表长度确定// 时间复杂度 O(max(m,n))， 空间复杂度是O(1)list* find(list* l1, int l1_len, list* l2, int l2_len) {  list* l1_next = l1, *l2_next = l2;    if ( l1_len > l2_len) {    for (int i = 0; i < l1_len - l2_len; i++) {      l1_next =  l1_next->next;    }  } else if (l1_len < l2_len) {    for (int i = 0; i < l2_len - l1_len; i++) {      l2_next =  l2_next->next;    }  }    do {    if (l1_next == l2_next)      return l1_next;    l1_next = l1_next->next;    l2_next = l2_next->next;  } while(l1_next && l2_next);  assert(l1_next == l2_next);  assert(l1_next == NULL);
  return NULL;}
// 2.链表长度不确定// 时间复杂度 O(2*max(m,n)) ，空间复杂度是O(1)list* find(list* l1, list* l2) {  int l1_len, l2_len  list* l1_next = l1, *l2_next = l2;  list* tmp, *ttmp;
  do {    if (l1_next == l2_next) {      return l1_next;    l1_next = l1_next->next;    l2_next = l2_next->next;  } while(l1_next && l2_next);
  if (l1_next ==NULL && l2_next == NULL)    return NULL;  tmp = l1_next == NULL ? l2 : ll;  ttmp = l1_next == NULL ? l2_next : ll_next;    while (ttmp->next) {    tmp = tmp->next;    ttmp = ttmp->next;  }  if (l1_next == NULL) {    l2_next = tmp;    l1_next = l1;  } else {    l1_next = tmp;    l2_next = l2;  }  assert(l1_next);  assert(l2_next);  do {    if (l1_next == l2_next) {      return l1_next;    }    l1_next = l1_next->next;    l2_next = l2_next->next;  } while(l1_next && l2_next);  assert(l1_next == l2_next);  assert(l1_next == NULL);
  return NULL;}