From d339eb17117df914796fdb3647fb591973f64e57 Mon Sep 17 00:00:00 2001
From: Jarrett Ye <jarrett.ye@outlook.com>
Date: Wed, 25 Dec 2024 09:47:27 +0800
Subject: [PATCH] Update src/optimal_retention.rs

Co-authored-by: Luc Mcgrady <lucmcgrady@gmail.com>
---
 src/optimal_retention.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/optimal_retention.rs b/src/optimal_retention.rs
index df73060..14f88f5 100644
--- a/src/optimal_retention.rs
+++ b/src/optimal_retention.rs
@@ -228,7 +228,7 @@ pub fn simulate(
         // Guards
         if card.due >= learn_span as f32 {
             if !is_learn {
-                let delta_t = learn_span - last_date_index;
+                let delta_t = learn_span.max(last_date_index) - last_date_index;
                 let pre_sim_days = (-card.last_date) as usize;
                 for i in 0..delta_t {
                     memorized_cnt_per_day[last_date_index + i] +=