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-rw-r--r--2019/day06.c19
1 files changed, 19 insertions, 0 deletions
diff --git a/2019/day06.c b/2019/day06.c
index fbfda57..2ae79fd 100644
--- a/2019/day06.c
+++ b/2019/day06.c
@@ -37,4 +37,23 @@ int main(void) {
 		orbits += ancestors(i);
 	}
 	printf("%zu\n", orbits);
+
+	size_t you[2048];
+	size_t ylen = 0;
+	for (size_t i = node("YOU"); i; i = tree[i].parent) {
+		you[ylen++] = i;
+	}
+	size_t san[2048];
+	size_t slen = 0;
+	for (size_t i = node("SAN"); i; i = tree[i].parent) {
+		san[slen++] = i;
+	}
+	for (size_t y = 0; y < ylen; ++y) {
+		for (size_t s = 0; s < slen; ++s) {
+			if (you[y] == san[s]) {
+				printf("%zu\n", y + s - 2);
+				return 0;
+			}
+		}
+	}
 }