update

day2.c

@@ -0,0 +1,54 @@
+#define DJSTD_BASIC_ENTRY
+#include "./djstdlib/core.c"
+
+int djstd_entry(Arena *arena, StringList args) {
+    string input = os_readEntireFile(arena, s("./day2-input"));
+
+    StringList ranges = strSplit(arena, s(","), input);
+
+    int64 result = 0;
+
+    for (EachEl(ranges, string, range)) {
+        if (range->length) {
+            StringList startStop = strSplit(arena, s("-"), *range);
+            if (startStop.length == 2) {
+                Int64Result start = parsePositiveInt64(startStop.data[0]);
+                Int64Result stop = parsePositiveInt64(startStop.data[1]);
+                if (start.valid && stop.valid) {
+                    for (int64 i = start.result; i <= stop.result; i++) {
+                        Scratch scratch = scratchStart(0, 0);
+                        string asStr = strPrintf(scratch.arena, "%zu", i);
+                        for (int j = 1; j <= asStr.length/2; j++) {
+                            if (asStr.length/j*j == asStr.length) {
+                                StringList list = PushList(scratch.arena, StringList, asStr.length/j);
+                                for (int k = 0; k < asStr.length/j; k++) {
+                                    ListAppend(list, strSlice(asStr, j * k, j*k + j));
+                                }
+                                string firstChunk = list.data[0];
+                                bool matched = true;
+                                for (EachEl(list, string, chunk)) {
+                                    if (!strEql(firstChunk, *chunk)) {
+                                        matched = false;
+                                        break;
+                                    }
+                                }
+                                if (matched) {
+                                    printStrList(list);
+                                    result += i;
+                                    i++;
+                                    break;
+                                }
+                            }
+                        }
+                        scratchEnd(scratch);
+                    }
+                }
+            }
+        }
+    }
+
+    println("%zu", result);
+
+    return 0;
+}
+