diff --git a/q4/q4_3b/q4_4.py b/q4/q4_3b/q4_4.py
new file mode 100644
index 0000000..7ad6650
--- /dev/null
+++ b/q4/q4_3b/q4_4.py
@@ -0,0 +1,12 @@
+import json
+import matplotlib.pyplot as plt
+
+with open("../q2_1_crawler/movies.json","r",encoding="utf-8") as f:
+    data = json.load(f)
+movies = data["movies"]
+
+dur = [i["duration"] for i in movies]
+plt.hist(dur,edgecolor="black")
+plt.xlabel("时长（分钟）")
+plt.savefig("q4_3b_hist.png",dpi=150)
+plt.close()
\ No newline at end of file