字符串序列的全排列

我们都知道全排列的定义：字符序列的所有组合。它的递归定义如下：序列A = {a1, a2, a3, ... an} ，Ai = A - {ai}，序列A的排列定义为Perm(A),

Perm(A) = a1Perm(A1) ,  a2Perm(A2),  a3Perm(A3)....anPerm(An);

由上面的递归定义可知，全排列可由递归实现，代码如下：

void Permutation(char *str, char *start)
{
    if (*start == 0)
    {
        cout<<str<<endl;
        return;
    }

    for (char * p = start; *p != 0; ++p)
    {
        char temp = *start;
        *start = *p;
        *p = temp;

        Permutation(str, start + 1);

        temp = *start;
        *start = *p;
        *p = temp;
    }
}

May 29, 2013 @lab