输出n对括号的所有有效(左右括号成对匹配)排列

void PrintBracketsPairRecs(char *pBegin, char *pCur, int nCurLeft)
{
    if (nCurLeft == 1)
        {
        *pCur = '(';
        *(pCur+1) = ')';
        printf("%s\n", pBegin); // exit of recursive function
        }
    else
        {
        // 1st way: ()*********
        *pCur = '(';
        *(pCur+1) = ')';
        PrintBracketsPairRecs(pBegin, pCur+2, nCurLeft-1);

        // 2nd way: (*********)
        *pCur = '(';
        *(pCur + (nCurLeft)*2 - 1) = ')';
        PrintBracketsPairRecs(pBegin, pCur+1, nCurLeft-1);
        }
}

void PrintBracketsPair(int n)
{
    char *pBuffer = new char[2 * n + 1];
    memset(pBuffer, 0, sizeof(char) * 2 * n + 1);
    PrintBracketsPairRecs(pBuffer, pBuffer, n);
    delete [] pBuffer;
}