diff --git a/q4_3b/zhifang_time.py b/q4_3b/zhifang_time.py
index 3ff0e69..d38f8e6 100644
--- a/q4_3b/zhifang_time.py
+++ b/q4_3b/zhifang_time.py
@@ -1,20 +1,20 @@
-import matplotlib.pyplot as plt
-import json
-duration=[]
-
-with open('movie.json', 'r', encoding='utf-8') as f:
-    data=json.load(f)
-    # print(data)
-    for i in data:
-       duration.append(i["duration"])
-
-plt.figure(figsize=(12,8))
-plt.hist( duration,                     # 数据
-         bins=10,                    # 分成几个柱子
-         color='#3498DB',            # 颜色
-         edgecolor='white')          # 柱子边框颜色
-plt.title('时长分布', fontsize=14)
-plt.xlabel('时长（分钟）', fontsize=13)
-plt.grid(True, linestyle='--', alpha=0.5, axis='y')
-plt.show()
-plt.savefig("q4_3b_hist.png",dpi=150,format='png')
\ No newline at end of file
+import matplotlib.pyplot as plt
+import json
+duration=[]
+
+with open('movie.json', 'r', encoding='utf-8') as f:
+    data=json.load(f)
+    # print(data)
+    for i in data:
+       duration.append(i["duration"])
+
+plt.figure(figsize=(12,8))
+plt.hist( duration,                     # 数据
+         bins=10,                    # 分成几个柱子
+         color='#3498DB',            # 颜色
+         edgecolor='white')          # 柱子边框颜色
+plt.title('时长分布', fontsize=14)
+plt.xlabel('时长（分钟）', fontsize=13)
+plt.grid(True, linestyle='--', alpha=0.5, axis='y')
+plt.savefig("q4_3b_hist.png",dpi=150,format='png')
+plt.show()