求助python大佬，那个牛牛找工作，这样写为什么一直出错

```
line_1 = input().split()
n,m = int(line_1[0]),int(line_1[1])
work_re = []
for i in range(n):
    line = input().split()
    work_re.append([int(x) for x in line])
m_cap = [int(x) for x in input().split()]
work_re.sort()
res = []
for i in m_cap:
    tag = None
    for j in work_re:
        if j[0] <= i:
            tag = j
    res.append(tag[1])
for p in res:
    print(p)

```