Initial commit

day1/puzzle1/main.c

@@ -0,0 +1,107 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <ctype.h>
+
+int two_char_two_interger(int a, int b)
+{
+    // int a is the 10's
+    // int b is the 1's
+    int num = (a * 10) + b;
+    printf("Got number: %i\n", num);
+    return num;
+}
+
+int main()
+{
+    const char *inputFile = "/home/ben/Documents/Projects/C/advent-of-code/day1/puzzle1/input";
+    int fd = open(inputFile, O_RDONLY);
+
+    if (fd < 0)
+    {
+        printf("\n\"%s \" could not open\n", inputFile);
+        exit(1);
+    }
+    struct stat statbuf;
+    int err = fstat(fd, &statbuf);
+    if (err < 0)
+    {
+        printf("\n\"%s \" could not open\n", inputFile);
+        exit(2);
+    }
+
+    char *ptr = mmap(NULL, statbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+    if (ptr == MAP_FAILED)
+    {
+        printf("Mapping Failed\n");
+        return 1;
+    }
+    int in_line = 0;
+    int first_num = -1;
+    int last_num;
+    char cur_char;
+    int total = 0;
+    // int numbers[1000];
+    int freePos = 0;
+
+    for (int i = 0; i < statbuf.st_size; i++)
+    {
+        if (in_line == 0)
+        {
+            in_line = 1;
+            for (i; i < __INT64_MAX__; i++)
+            {
+                cur_char = ptr[i];
+                if isdigit (cur_char)
+                {
+                    if (first_num == -1)
+                    {
+                        // We have not set a first number yet
+                        first_num = (int)cur_char - '0';
+                        last_num = (int)cur_char - '0';
+                        continue;
+                    }
+
+                    last_num = (int)cur_char - '0';
+                }
+                if (cur_char == 0x0A)
+                {
+                    if (last_num != -1)
+                    {
+                        // printf("First num = %i\t", first_num);
+                        // printf("Last num = %i\n", last_num);
+                        total += two_char_two_interger(first_num, last_num);
+                    }
+                    first_num = -1;
+                    last_num = -1;
+                    in_line = 0;
+                    // printf("Line break\n");
+                    break;
+                }
+            }
+        }
+
+        // printf("%X\n", ptr[i]);
+    }
+    printf("Total is: %i\n", total);
+    // ssize_t n = write(1, ptr, statbuf.st_size);
+    // if (n != statbuf.st_size)
+    // {
+    //     printf("Write Failed");
+    // }
+
+    err = munmap(ptr, statbuf.st_size);
+
+    if (err != 0)
+    {
+        printf("Unmapping Failed\n");
+        return 1;
+    }
+
+    close(fd);
+
+    return 0;
+}