Index: aoc2024.c
==================================================================
--- aoc2024.c
+++ aoc2024.c
@@ -8,10 +8,13 @@
 #include "aocutils.h"
 
 /* === aoc202406 =======================================================
    Hmmm, I've done something like this already this year... on day 4
    I need rcmap() moved to aocutils ... done; now it's called `linearize2d`
+Part Two: brute force? It likely is faster than coming up with an algo
+   Let's go: save map, for every available position put in an obstacle,
+   loop around until some place is visited 4? times or area is exited
 ===================================================================== */
 
 static bool validpos(unsigned s, int r, int c) {
     if (r < 0) return false;
     if (c < 0) return false;
@@ -24,11 +27,12 @@
     if (*drow) { *dcol = -*drow; *drow = 0; }
     else       { *drow =  *dcol; *dcol = 0; }
 }
 
 void aoc202406(char *data, size_t len) {
-    (void)len;
+    char *savedmap = malloc(len + 1);
+    strcpy(savedmap, data);
     // assume data is well-formatted and has the same number of rows and columns
     unsigned size = 1 + strchr(data, '\n') - data;
     unsigned linear_pos = strchr(data, '^') - data;
     int row_pos = (int)(linear_pos / size);
     int col_pos = (int)(linear_pos % size);
@@ -47,10 +51,12 @@
                       col_pos += deltacol;
                       break;
         }
     }
     printf("The guard visits %u positions before leaving the area.\n", visited);
+    // Part Two
+    free(savedmap);
 }
 
 /* === aoc202405 =======================================================
 ===================================================================== */