1 files changed, 3 insertions, 3 deletions

diff --git a/2024/12/day12a.cpp b/2024/12/day12a.cpp
index b972fd2..89cc3d9 100644
--- a/2024/12/day12a.cpp
+++ b/2024/12/day12a.cpp
@@ -46,8 +46,8 @@ public:
                 cells = new char[M * N];
                 for (int i = 0; i < N; i++) {
                         for (int j = 0; j < M; j++) {
-                                region[N*i + j] = -1;
-                                cells[N*i + j] = j < (int)lines[i].size() ?
+                                region[M*i + j] = -1;
+                                cells[M*i + j] = j < (int)lines[i].size() ?
                                     lines[i][j] : out_of_bound;
                         }
                 }
@@ -74,7 +74,7 @@ private:
 
         int coord(pair<int, int> p) {
                 auto [i, j] = p;
-                return i >= N || i < 0 || j >= M || j < 0 ? -1 : N*i + j;
+                return i >= N || i < 0 || j >= M || j < 0 ? -1 : M*i + j;
         }
 };