数据结构实现大数相减
时间: 2024-01-04 07:04:00 浏览: 27
大数相减可以通过字符串的比较和减法操作来实现。以下是一个实现大数相减的示例代码:
```python
def isLess(a, b):
if len(a) == len(b):
return a < b
return len(a) < len(b)
def subStrings(num1, num2):
res = ""
if isLess(num1, num2):
res = subStrings(num2, num1)
res = "-" + res
else:
carry = 0
i = len(num1) - 1
j = len(num2) - 1
while i >= 0 or j >= 0:
digit1 = int(num1[i]) if i >= 0 else 0
digit2 = int(num2[j]) if j >= 0 else 0
diff = digit1 - digit2 - carry
if diff < 0:
diff += 10
carry = 1
else:
carry = 0
res = str(diff) + res
i -= 1
j -= 1
return res
num1 = "123456789"
num2 = "987654321"
result = subStrings(num1, num2)
print(result) # 输出:-864197532
```