diff --git a/src/fast_grnn.c b/src/fast_grnn.c
index 0c84bdf..da7e9b7 100644
--- a/src/fast_grnn.c
+++ b/src/fast_grnn.c
@@ -69,9 +69,9 @@ void sha_rnn_rnn0_process(const sha_rnn_input_t input, sha_rnn_rnn1_input_t outp
 
     for (size_t k = 0; k < SHARNN_BRICK_SIZE; k++)
     {
-        memset(output, 0, sizeof(float) * 64);
+        memset(output, 0, sizeof(sha_rnn_rnn1_input_t));
         rnn0_process(input[k], hidden, output);
-        memcpy(hidden, output, sizeof(float) * 64);
+        memcpy(hidden, output, sizeof(hidden));
     }
 }
 
@@ -109,17 +109,17 @@ static void rnn1_process(const float input[64], const float hidden[32], float ou
 
 void sha_rnn_rnn1_process(const sha_rnn_rnn1_input_t input, sha_rnn_fc_input_t output)
 {
-    static float rnn1_input_hist[9][64];
-    static size_t rnn1_hist_idx;
+    static sha_rnn_rnn1_input_t rnn1_input_hist[9];
+    static size_t rnn1_hist_idx = 0;
 
     float rnn1_hidden[32] = {0.0};
 
     memcpy(rnn1_input_hist[rnn1_hist_idx], input, sizeof(sha_rnn_rnn1_input_t));
-    memset(output, 0, sizeof(sha_rnn_fc_input_t));
 
     for (size_t i = 0; i < 9; i++)
     {
         size_t j = (rnn1_hist_idx + 1 + i) % 9;
+        memset(output, 0, sizeof(sha_rnn_fc_input_t));
         rnn1_process(rnn1_input_hist[j], rnn1_hidden, output);
         memcpy(rnn1_hidden, output, sizeof(sha_rnn_fc_input_t));
     }