Create 2.c

LeetCode-CN/2.c

@@ -0,0 +1,75 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     struct ListNode *next;
+ * };
+ */
+#ifdef __cplusplus
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#endif
+typedef struct ListNode ListNode;
+
+ListNode* BigIntegerAdd(ListNode* a, ListNode* b,
+    int* tmp)
+{
+    ListNode* pa = a;
+    ListNode* pb = b;
+    int pos = 0;
+    while (pa != NULL && pb != NULL)
+    {
+        tmp[pos] = pa->val + pb->val;
+        pa = pa->next;
+        pb = pb->next;
+        pos++;
+    }
+    while (pa != NULL)
+    {
+        tmp[pos] = pa->val;
+        pa = pa->next;
+        pos++;
+    }
+    while (pb != NULL)
+    {
+        tmp[pos] = pb->val;
+        pb = pb->next;
+        pos++;
+    }
+    ListNode* head = NULL;
+    ListNode** pthis = &head;
+    for (int i = 0; i < pos; i++)
+    {
+        if (tmp[i] >= 10)
+        {
+            tmp[i + 1] += tmp[i] / 10;
+            tmp[i] %= 10;
+        }
+
+        (*pthis) = (ListNode*)malloc(sizeof(ListNode));
+        (*pthis)->val = tmp[i];
+        (*pthis)->next = NULL;
+        pthis = &((*pthis)->next);
+    }
+
+    if (tmp[pos] > 0)
+    {
+        (*pthis) = (ListNode*)malloc(sizeof(ListNode));
+        (*pthis)->val = tmp[pos];
+        (*pthis)->next = NULL;
+        pthis = &((*pthis)->next);
+    }
+
+    return head;
+}
+
+struct ListNode* addTwoNumbers(struct ListNode* l1, struct ListNode* l2) {
+    int tmp[1024];
+    memset(tmp, 0, sizeof(tmp));
+    return BigIntegerAdd(l1, l2, tmp);
+}