#include<iostream>
#include<string>
using namespace std;
void DFA(int, int, string);
int main()
{
    string s;
    cin >> s;
    DFA(0, 1, s);
    system("pause");
    return 0;
}

void DFA(int x, int y, string s)//采用递归的方法
{
    int i = 0;
    for (i = 0; i < s.length(); i++)//多处采用for是为了保证关键字的优先级
        if (s[i] == ‘|‘)//如果s[i]==‘|’，则将字符串s分隔开，如 ‘a|b‘的话，将字符串分隔为s1=a;s2=b;并再次进行递归 ，递归结束的条件为s[i]！=’|‘
        {
            string s1(s, 0, i - 1);
            string s2(s, i + 1);
            DFA(x, y, s1); DFA(x, y, s2);
        }
    for (i = 0; i < s.length(); i++)//同上,递归结束条件为是s[i]!=’.‘
        if (s[i] == ‘.‘)
        {
            string s1(s, i - 1, 1);
            string s2(s, i + 1, 1);
            DFA(x, y + 1, s1); DFA(y + 1, y, s2);
        }
    for (i = 0; i < s.length(); i++)//同上,递归结束条件为s[i]！=’*‘
    {
        if (s[i] == ‘*‘)
        {
            string s1("~");
            string s2(s, i - 1, 1);
            DFA(x, y + 2, s1);
            DFA(y + 2, y + 2, s2);
            DFA(y + 2, y, s1);
        }
    }
    if (s.length() == 1)//确保最后不会输出整个字符串
        cout << "f(" << x << "," << s << ")=" << y << endl;
}