solved part 2, low-ish runtime

6_2/main.c

@@ -0,0 +1,106 @@
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <time.h>
+#include <limits.h>
+
+char input[] =
+{
+#embed "input.txt"
+,'\0' // null terminator
+};
+
+int width = 0;
+int height = 0;
+uint64_t result = 0;
+
+
+uint64_t parseNumVert(char* str, int len, int lines){
+    int i = 0;
+    while(str[i] == ' '){
+        i+=len;
+    }
+    uint64_t out = 0;
+    while((i/len)<lines && str[i] != ' '){
+        //printf("%c", str[i]);
+        out += str[i]-0x30;
+        out *= 10;
+        i+=len;
+    }
+    out /=10;
+    //printf("\t%lu\n", out);
+    return out;
+}
+
+int main(int argc, char *argv[]){
+    clock_t start, end;
+    start = clock();
+
+
+    while(input[width] != '\n'){
+        width++;
+    }
+
+    //printf("width: %d\n", width);
+    //parse ranges first
+    int i = 0;
+    int lines = 0;
+    while(input[i+1] != 0){
+        lines++;
+        i+=(width+1);
+    }lines--;
+
+
+    char* symbols = input+(width+1)*(lines-1);
+    //printf("line count: %d\n", lines);
+    //printf("symbols:\n%s\n", symbols);
+
+    //printf("parsing the first number: %lu\n", parseNumVert(input, width+1, lines));
+
+
+    int parse_length = 1;
+    uint64_t col_res = 0;;
+    while(*symbols != 0){
+        while(symbols[parse_length] == ' ' || symbols[parse_length] == '\n'){
+            parse_length++;
+        }
+        parse_length--;
+        //printf("parsing %d long numbers\n", parse_length);
+        
+        if(*symbols == '*'){
+            col_res = 1;
+            //printf("multiplying....\n");
+            for(int i = 0; i<parse_length; i++){
+                uint64_t num = parseNumVert(symbols-(lines*(width+1))+i, width+1, lines);
+                //printf("parsed %lu\n", num);
+                col_res *= num; 
+            }
+        }else if(*symbols == '+'){
+            col_res = 0;
+            //printf("adding....\n");
+            for(int i = 0; i<parse_length; i++){
+                uint64_t num = parseNumVert(symbols-(lines*(width+1))+i, width+1, lines);
+                //printf("parsed %lu\n", num);
+                col_res += num;
+            }
+        }
+        //printf("total: %lu\n", col_res);
+        result += col_res;
+        symbols += parse_length+1;
+        parse_length = 1;
+    }
+
+    end = clock();
+    printf("count: %lu\n", result);
+    clock_t ticks_taken = end - start; 
+    double time_taken = ((double)ticks_taken)/CLOCKS_PER_SEC;
+    printf("time take: %f ticks\n", time_taken);
+    printf("CLOCKS_PER_SEC: %ld\n", CLOCKS_PER_SEC);
+
+
+    exit(1);
+}