洛谷P3719 REXP 题解

题目

一道考验递归的题目，在面对这种字符串处理的题时，还是应该用递归这种比较好看懂而且比较简单写的算法。

\(code\)

```c++
// luogu-judger-enable-o2

include

include

include

include

include

define int long long

using namespace std;
int digui(int ans)
{
char c;
while (cin >> c)
{
if (c == ')') return ans;
if (c == 'a') ans++;
if (c == '(') ans += digui(0);
if (c == '|') return ans = max(ans, digui(0));//因为最外圈可能没有括号，所以必须return
}
return ans;
}
signed main()
{
printf("%lld", digui(0));
}