Index: aoc2024.c
==================================================================
--- aoc2024.c
+++ aoc2024.c
@@ -5,15 +5,29 @@
 #include <stdlib.h>
 #include <string.h>
 #include "aocdailies.h"
 #include "aocutils.h"
 
+static int ppcmp(unsigned a, unsigned b, unsigned (*r)[2], size_t nr) {
+    for (size_t k = 0; k < nr; k++) {
+        if ((a == r[k][0]) && (b == r[k][1])) return -1;
+        if ((a == r[k][1]) && (b == r[k][0])) return 1;
+    }
+    return 0;
+}
+
+// can't be bothered to do anything other than bubble sort
 static void reorder(unsigned *a, size_t na, unsigned (*r)[2], size_t nr) {
-    (void)a;
-    (void)na;
-    (void)r;
-    (void)nr;
+    for (size_t range = na; --range > 0; /*void*/) {
+        for (size_t outer = 0; outer < range; outer++) {
+            if (ppcmp(a[outer], a[outer+1], r, nr) > 0) {
+                unsigned tmp = a[outer];
+                a[outer] = a[outer+1];
+                a[outer+1] = tmp;
+            }
+        }
+    }
 }
 
 static const unsigned *vfind(unsigned v, const unsigned *a, size_t n) {
     for (size_t k = 0; k < n; k++) {
         if (a[k] == v) return a + k;
@@ -22,27 +36,19 @@
 }
 
 void aoc202405(char *data, size_t len) {
     (void)len; // unused argument
     unsigned pagepair[1200][2], npp = 0; // 1200 works for me
-    unsigned ppcount[100][2] = {0}; // assume all page numbers < 100
     char *line = strtok(data, "\n");
     while (strchr(line, '|')) {
         char *err;
         pagepair[npp][0] = strtoul(line, &err, 10);
-        ppcount[pagepair[npp][0]][0]++;
         err += 1; // skip '|'
         pagepair[npp][1] = strtoul(err, &err, 10);
-        ppcount[pagepair[npp][1]][1]++;
         npp++;
         line = strtok(NULL, "\n");
     }
-    for (unsigned k = 0; k < 100; k++) {
-        if (ppcount[k][0] + ppcount[k][1])
-              printf("%u: [%u, %u]  ", k, ppcount[k][0], ppcount[k][1]);
-    }
-    printf("\n");
     unsigned update[32], nupdates; // 32 works for me
     unsigned accumsum = 0, accumsum2 = 0;
     do {
         nupdates = 0;
         char *err = line;
@@ -66,12 +72,12 @@
                 break;
             }
         }
         accumsum += accum;
     } while ((line = strtok(NULL, "\n")) != NULL);
-    printf("The sum of middle update numbers is {%u}\n", accumsum);
-    printf("The sum of middle update numbers for newly ordered updates is {%u}\n", accumsum2);
+    printf("The sum of middle update numbers is {%u}.\n", accumsum);
+    printf("The sum of middle update numbers for newly ordered updates is {%u}.\n", accumsum2);
 }
 
 static size_t rcmap(unsigned size, unsigned row, unsigned col) {
     return row * (size + 1) + col;
 }