Problem 2: add two numbers
This commit is contained in:
parent
b7e708b5b7
commit
e1dedc1464
5 changed files with 149 additions and 0 deletions
1
problems/2-add-two-numbers/Makefile
Symbolic link
1
problems/2-add-two-numbers/Makefile
Symbolic link
|
@ -0,0 +1 @@
|
|||
../template/Makefile
|
45
problems/2-add-two-numbers/lib.c
Normal file
45
problems/2-add-two-numbers/lib.c
Normal file
|
@ -0,0 +1,45 @@
|
|||
#include <stdlib.h>
|
||||
#include "lib.h"
|
||||
|
||||
struct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2) {
|
||||
struct ListNode* current = NULL;
|
||||
struct ListNode* first_node = NULL;
|
||||
|
||||
int reminder = 0;
|
||||
while (l1 != NULL || l2 != NULL || reminder != 0) {
|
||||
// Read digits
|
||||
int a = 0;
|
||||
int b = 0;
|
||||
if (l1 != NULL)
|
||||
a = l1->val;
|
||||
if (l2 != NULL)
|
||||
b = l2->val;
|
||||
|
||||
// Move pointers to the next node
|
||||
if (l1 != NULL)
|
||||
l1 = l1->next;
|
||||
if (l2 != NULL)
|
||||
l2 = l2->next;
|
||||
|
||||
// Calculate the result
|
||||
int digit = (a + b + reminder) % 10;
|
||||
reminder = (a + b + reminder) / 10;
|
||||
|
||||
// Create the first node
|
||||
if (current == NULL) {
|
||||
current = malloc(sizeof(struct ListNode));
|
||||
first_node = current;
|
||||
}
|
||||
// Create regular node
|
||||
else {
|
||||
current->next = malloc(sizeof(struct ListNode));
|
||||
current = current->next;
|
||||
}
|
||||
|
||||
// Save the result
|
||||
current->val = digit;
|
||||
current->next = NULL;
|
||||
}
|
||||
|
||||
return first_node;
|
||||
}
|
8
problems/2-add-two-numbers/lib.h
Normal file
8
problems/2-add-two-numbers/lib.h
Normal file
|
@ -0,0 +1,8 @@
|
|||
#pragma once
|
||||
|
||||
struct ListNode {
|
||||
int val;
|
||||
struct ListNode *next;
|
||||
};
|
||||
|
||||
struct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2);
|
86
problems/2-add-two-numbers/main.c
Normal file
86
problems/2-add-two-numbers/main.c
Normal file
|
@ -0,0 +1,86 @@
|
|||
#include <stdlib.h>
|
||||
#include <stdio.h>
|
||||
#include "lib.h"
|
||||
|
||||
// Creates single node
|
||||
struct ListNode* mkNode(int val) {
|
||||
struct ListNode* node = malloc(sizeof(struct ListNode));
|
||||
node->val = val;
|
||||
node->next = NULL;
|
||||
return node;
|
||||
}
|
||||
|
||||
// Creates linked list
|
||||
struct ListNode* mkList(int* nums, int length) {
|
||||
struct ListNode* first = NULL;
|
||||
struct ListNode* current = NULL;
|
||||
for (int i=0; i<length; i++) {
|
||||
// First node
|
||||
if (current == NULL) {
|
||||
current = mkNode(nums[i]);
|
||||
first = current;
|
||||
}
|
||||
// Regular node
|
||||
else {
|
||||
current->next = mkNode(nums[i]);
|
||||
current = current->next;
|
||||
}
|
||||
}
|
||||
return first;
|
||||
}
|
||||
|
||||
// Returns 1 if linked lists are equal.
|
||||
// Returns 0 otherwise.
|
||||
int cmpLists(struct ListNode* a, struct ListNode* b) {
|
||||
while (a != NULL || b != NULL) {
|
||||
// Both nodes exist
|
||||
if (a == NULL || b == NULL)
|
||||
return 0;
|
||||
|
||||
// Check values
|
||||
if (a->val != b->val)
|
||||
return 0;
|
||||
|
||||
// Go to next node
|
||||
a = a->next;
|
||||
b = b->next;
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
// Free allocated memory
|
||||
void freeLinkedList(struct ListNode* list) {
|
||||
struct ListNode* current;
|
||||
while (list != NULL) {
|
||||
current = list;
|
||||
list = list->next;
|
||||
free(current);
|
||||
}
|
||||
}
|
||||
|
||||
int main() {
|
||||
// First list
|
||||
int a[] = {2, 4, 3};
|
||||
struct ListNode* list_a = mkList(a, 3);
|
||||
|
||||
// Second list
|
||||
int b[] = {5, 6, 4};
|
||||
struct ListNode* list_b = mkList(b, 3);
|
||||
|
||||
// Expected sum
|
||||
int c[] = {7, 0, 8};
|
||||
struct ListNode* list_c = mkList(c, 3);
|
||||
|
||||
// Computed result
|
||||
struct ListNode* res = addTwoNumbers(list_a, list_b);
|
||||
|
||||
printf("Test 1: %d\n", cmpLists(res, list_c));
|
||||
|
||||
freeLinkedList(list_a);
|
||||
freeLinkedList(list_b);
|
||||
freeLinkedList(list_c);
|
||||
freeLinkedList(res);
|
||||
|
||||
return 0;
|
||||
}
|
9
problems/2-add-two-numbers/readme.md
Normal file
9
problems/2-add-two-numbers/readme.md
Normal file
|
@ -0,0 +1,9 @@
|
|||
# 2. Add two numbers
|
||||
|
||||
* [Leetcode](https://leetcode.com/problems/add-two-numbers/)
|
||||
|
||||
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 contains a single digit.
|
||||
Add the two numbers and return the sum as a linked list.
|
||||
|
||||
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
|
Loading…
Reference in a new issue