Problem:
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
Example:
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
Explanation: 342 + 465 = 807.
思路:
Solution (C++):
ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
ListNode l(0);
ListNode* l3 = &l, *p = &l;
int sum = 0, carry = 0;
while (l1 && l2 ) {
sum = l1->val + l2->val + carry;
carry = sum / 10;
sum %= 10;
p->next = new ListNode(sum);
p = p->next;
l1 = l1->next;
l2 = l2->next;
}
if (l1) {
while (l1) {
sum = l1->val + carry;
carry = sum / 10;
sum %= 10;
p->next = new ListNode(sum);
p = p->next;
l1 = l1->next;
}
}
if (l2) {
while (l2) {
sum = l2->val + carry;
carry = sum / 10;
sum %= 10;
p->next = new ListNode(sum);
p = p->next;
l2 = l2->next;
}
}
if (!l1 && !l2 && carry) { p->next = new ListNode(carry); p = p->next; }
return l3->next;
}
性能:
Runtime: 28 ms Memory Usage: 9.4 MB
思路:
Solution (C++):
性能:
Runtime: ms Memory Usage: MB