python代码提交pta平台显示非零返回怎么改？

Question

pta结果显示非零返回，如何修改
题目地址(https://pintia.cn/problem-sets/994805046380707840/exam/problems/994805136889593856)
代码：

```python

s = input()
pinyin = {
    '0': 'ling',
    '1': 'yi',
    '2': 'er',
    '3': 'san',
    '4': 'si',
    '5': 'wu',
    '6': 'liu',
    '7': 'qi',
    '8': 'ba',
    '9': 'jiu'
}
i = 0
num = int(s)
if num < 0:
    print("fu", end=' ')
    for i in range(1, len(s) - 1):
        print(pinyin[s[i]], end=' ')
    print(pinyin[s[i + 1]], end='')
elif num == 0:
    print("ling", end='')
else:
    for i in range(len(s) - 1):
        print(pinyin[s[i]], end=' ')
    print(pinyin[s[i + 1]], end='')
exit(0)

```

Answer 1

s = input()
pinyin = {
    '-':'fu',
    '0': 'ling',
    '1': 'yi',
    '2': 'er',
    '3': 'san',
    '4': 'si',
    '5': 'wu',
    '6': 'liu',
    '7': 'qi',
    '8': 'ba',
    '9': 'jiu'
}
a=[pinyin[x] for x in s]
print(' '.join(a))

这样就行了，写多错多