/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
	}
}

LyogcGFja2FnZSB3aGF0ZXZlcjsgLy8gZG9uJ3QgcGxhY2UgcGFja2FnZSBuYW1lISAqLwoKaW1wb3J0IGphdmEudXRpbC4qOwppbXBvcnQgamF2YS5sYW5nLio7CmltcG9ydCBqYXZhLmlvLio7CgovKiBOYW1lIG9mIHRoZSBjbGFzcyBoYXMgdG8gYmUgIk1haW4iIG9ubHkgaWYgdGhlIGNsYXNzIGlzIHB1YmxpYy4gKi8KY2xhc3MgSWRlb25lCnsKCXB1YmxpYyBzdGF0aWMgdm9pZCBtYWluIChTdHJpbmdbXSBhcmdzKSB0aHJvd3MgamF2YS5sYW5nLkV4Y2VwdGlvbgoJewoJCS8vIHlvdXIgY29kZSBnb2VzIGhlcmUKCX0KfQ==

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

import matplotlib.pyplot as plt

# 设置中文字体
plt.rcParams['font.sans-serif'] = ['SimHei']
plt.rcParams['axes.unicode_minus'] = False

# 创建数据
semesters = ['2019春季', '2019秋季', '2020春季', '2020秋季', '2021春季', '2021秋季']
homework_count = [150, 170, 190, 210, 230, 250]

# 创建图表
plt.figure(figsize=(10, 6))
plt.plot(semesters, homework_count, marker='o', linestyle='-', color='b', linewidth=2)

# 添加数据标签
for x, y in zip(semesters, homework_count):
    plt.text(x, y, f'{y}', ha='center', va='bottom')

# 添加网格线
plt.grid(True, linestyle='--', alpha=0.6)

# 添加标题和标签
plt.title('教师作业批改量变化趋势 (2019 - 2021)', fontsize=16)
plt.xlabel('学期', fontsize=12)
plt.ylabel('每周批改作业量 (份)', fontsize=12)

# 显示图表
plt.show()