Python列表切片/copy()赋值后被识别为整数，逐科目取最高分问题求解

错误原因 #

你遇到的a/b/c变量为int类型的问题，和copy()、切片复制方法本身无关，是变量赋值逻辑错误：

• subject_score = [0, 0, 0, 0, 0]是长度为5的整数列表，subject_score[:]切片后返回的还是包含5个整数的列表
• 直接用a, b, c = subject_score[:]解包时，Python会将列表内的前三个整数0依次赋值给a、b、c，三个变量自然都是int类型，后续执行a[i]这类列表操作就会报错

修复方法 #

如果需要a、b、c为三个独立的、初始值和subject_score一致的列表，要分别进行三次拷贝：

subject_score = [0, 0, 0, 0, 0]
a = subject_score.copy()
b = subject_score.copy()
c = subject_score.copy()
# 也可以用切片写法：a = subject_score[:]

额外问题修复 #

你原有代码还有其他可修正的问题：

1. 字符串和整数不能直接拼接，输出时需要将最高分转为字符串，比如print("Math:"+ str(minscore1))
2. range(0, len(subject_score) - 1)会漏掉列表最后一个元素，应改为range(0, len(subject_score))
3. 不需要手动循环计算最大值，直接用Python内置的max()函数即可简化代码

完整可运行代码（符合需求） #

以下代码实现了从输入录入分数、统计每个科目最高分的完整功能：

subjects = ["数学", "英语", "科学"]
score_count = 5
all_scores = []

# 录入分数
for sub in subjects:
    print(f"请输入{sub}的{score_count}个分数：")
    sub_scores = []
    for _ in range(score_count):
        sub_scores.append(int(input()))
    all_scores.append(sub_scores)

# 输出最高分
for idx, sub_name in enumerate(subjects):
    best_score = max(all_scores[idx])
    print(f"{sub_name} Best Score: {best_score}")

如果你需要保留原有代码的逻辑，修复后的版本如下：

subject_score = [0, 0, 0, 0, 0]
# 正确初始化三个列表
a = subject_score[:]
b = subject_score[:]
c = subject_score[:]
# 示例分数数据，可替换为你自己的输入逻辑
midterm_score = [
    [0,20,30,40,50],
    [0,40,50,80,90],
    [0,90,78,90,97]
]

for i in range(len(subject_score)):
    a[i] = midterm_score[0][i]
    b[i] = midterm_score[1][i]
    c[i] = midterm_score[2][i]

# 计算数学最高分
minscore1 = a[0]
for i in range(1, len(subject_score)):
    if minscore1 < a[i]:
        minscore1 = a[i]
# 计算英语最高分
minscore2 = b[0]
for i in range(1, len(subject_score)):
    if minscore2 < b[i]:
        minscore2 = b[i]
# 计算科学最高分
minscore3 = c[0]
for i in range(1, len(subject_score)):
    if minscore3 < c[i]:
        minscore3 = c[i]

print(a, b, c)
print("Math:" + str(minscore1))
print("English:" + str(minscore2))
print("Science:" + str(minscore3))

内容的提问来源于stack exchange，提问作者J.Moon