大整数加法

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

typedef struct Point{
int digit;
struct Point* next;
} CPoint;

int main(void){
CPoint* src_head, *src_tail;
CPoint* dst_head, *dst_tail;
CPoint* prev;
int carry;
Char src_num[2000];
Char dst_num[2000];
scanf("%s",src_num);
scanf("%s",dst_num);
int src_len = strlen(src_num);
int dst_len = strlen(dst_num);
for (i = src_len-1; i>=0; i--){
prev = src_head;
src_head = (CPoint*)malloc(size(CPoint));
src_head->digit=src_num[i]-'0';
if(src_tail == null){
src_tail = src_head;
src_head->next = null;
}else{
prev->next = src_head;
src_head->next = null;