poj.openjudge.cn/practice/1001

#include <iostream>
#include <cctype>
#include <stack>
#include <cassert>
#include <string>

int main()
{
    using namespace std;
    char c;
    stack<char> symbol;
    while (cin.get(c) && isalpha(c))
        cout << c;
    cin.putback(c);
    cout << ' ';

    string sth;
    bool flag = false;
    while ( (cin >> c) && (c != ';')) {
        if (c == ')') {
            flag = true;
            while (true) {
                assert(!symbol.empty() && "括号不匹配");
                switch (symbol.top())
                {
                case '*': cout << "->"; break;
                case 'c': cout << "const"; break;
                case '(': goto EXIT;
                default : assert(false && "未知字符");
                }
                symbol.pop();
            }
EXIT:
        symbol.pop();
        } else if (flag) {
            if (c == '(') {
                cout << c;
                int count = 1;
                while (count != 0) {
                    cin >> c;
                    if (c == '(')
                        ++count;
                    else if (c == ')')
                        --count;
                    cout << c;
                }
            } else {
                cout << c;
            }
        } else {
            if (c == '*' || c == '(') {
                symbol.push(c);
            } else {
                assert((isalnum(c) || c=='_') && "非标识符");
                sth = c;
                while (c = cin.peek(), isalnum(c) || c=='_') {
                    cin.ignore();
                    sth.push_back(c);
                }
                if (sth == "const") {
                    symbol.push('c');
                } else {
                    cout << sth << ':';
                    flag = true;
                }
            }
        }
    }
    while (!symbol.empty()) {
        switch (symbol.top()) {
            case 'c': cout << "const"; break;
            case '*': cout << "->"; break;
            case '(': assert(false && "括号不匹配"); break;
            default : assert(false && "未知字符");
        }
        symbol.pop();
    }
    cout << ';' << endl;
}