diff --git a/aoc/2024/05/part-one.c b/aoc/2024/05/part-one.c
new file mode 100644
index 0000000..4d2b560
--- /dev/null
+++ b/aoc/2024/05/part-one.c
@@ -0,0 +1,27 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+ bool after[100][100] = {false};
+ unsigned char x, y;
+ while (scanf("%hhu|%hhu\n", &x, &y) == 2)
+ after[y][x] = true;
+
+ unsigned char line[90];
+ unsigned sum = y = 0;
+ do {
+ bool right = true;
+ do {
+ line[y] = x;
+ for (unsigned char i = 0; right && i < y; ++i)
+ if (after[line[i]][line[y]])
+ right = false;
+ } while (scanf(",%hhu", &x) == 1 && ++y);
+ if (right)
+ sum += line[y + 1 >> 1];
+ } while (y = 0, scanf("%hhu", &x) == 1);
+ printf("%u\n", sum);
+ return 0;
+}
diff --git a/aoc/2024/05/part-two.c b/aoc/2024/05/part-two.c
new file mode 100644
index 0000000..443e8b0
--- /dev/null
+++ b/aoc/2024/05/part-two.c
@@ -0,0 +1,35 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static bool after[100][100];
+
+int compare(const void *x, const void *y)
+{
+ return after[*(const unsigned char *) x][*(const unsigned char *) y];
+}
+
+int main()
+{
+ unsigned char x, y;
+ while (scanf("%hhu|%hhu\n", &x, &y) == 2)
+ after[y][x] = true;
+
+ unsigned char line[90];
+ unsigned sum = y = 0;
+ do {
+ bool right = true;
+ do {
+ line[y] = x;
+ for (unsigned char i = 0; right && i < y; ++i)
+ if (after[line[i]][line[y]])
+ right = false;
+ } while (scanf(",%hhu", &x) == 1 && ++y);
+ if (right)
+ continue;
+ qsort(line, ++y, 1, compare);
+ sum += line[y >> 1];
+ } while (y = 0, scanf("%hhu", &x) == 1);
+ printf("%u\n", sum);
+ return 0;
+}
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