学步园

/*----------------------------------------

		随机生成文本程序
		2011.3.15 by LiWang112358

----------------------------------------*/

#include <iostream>
#include <time.h>

using namespace std;


int k = 2;//二元模型；当前单词的产生依赖于前一个单词
char inputchars[5000000];
char * word[1000000];
int nword = 0;

int cmp(char * p,char * q)
{
	int n = k;
	for (; *p == *q; p ++ ,q ++)
		if ( 0 == *p && -- n == 0)//只有当后缀数组的前两个单词相同时，默认是相同的
			return 0;
	return *p - *q;
}

int sortcmp(const void * p,const void * q)
{
	return cmp((char *)p,(char *)q) <= 0;
}

void myQsort(char * a[],int l,int r)
{
    int i,j;
	char * s = a[l];
    i=l;
    j=r;
    while (i<=j)
    {
        while (cmp(a[i],s) < 0 && i<=j) i++;
        while (cmp(a[j],s) > 0 && i<=j) j--;
        if (i<=j)
        {
            swap(a[i],a[j]);
            i++;
            j--;
        }
    }
    if (i<r) myQsort(a,i,r);
    if (l<j) myQsort(a,l,j);
}

int find(int begin,int end,char * x,char * a[]) // 二分查找
{
	int l = begin,r = end,mid = (l + r) >> 1;

	while (l <= r)
	{
		if (strcmp(a[mid],x) < 0) l = mid + 1;
		else if (strcmp(a[mid],x) > 0) r = mid - 1;
		else if (strcmp(a[mid],x) == 0)
		{
			while (mid > 0 && strcmp(a[mid],a[mid - 1]) == 0) --mid;
			return mid;
		}
		mid = (l + r) >> 1;
	}
	return -1;
}

char * skip(char * p,int num)
{
	for (int i = 0; i < num ; ++ i)
	{
		for (; (*p) > 0; ++ p);
		p++;
	}
	return p;
}
int main()
{
	freopen("in.txt","r",stdin);

	memset(inputchars,0,sizeof(inputchars));
	word[0] = inputchars;
	while (scanf("%s",word[nword]) != EOF)
	{
		word[nword + 1] = word[nword] + strlen(word[nword]) + 1;
		nword ++;
	}
	for (int i = 0; i < k; ++ i)
		word[nword][i] = 0;
	myQsort(word,0,nword - 1);

	srand(int(time(0)));
	char * p = inputchars;

	for (int i = 0; i < 10000; ++ i)
	{
		printf("%s ",p);
		if ( i > 0 && i % 20 == 0) printf("/n");
		int pos = find(0,nword - 1,p,word);
		int j = 0;
		for (j = 0; strcmp(p,word[pos + j]) == 0 && pos + j < nword; ++ j);

		int rd = abs(rand()) % j;
		p = word[pos + rd];
		p = skip(p,1);
		if (strlen(skip(p,k - 1)) == 0) break;
	}

	return 0;
}

转自：http://blog.csdn.net/liwang112358/article/details/6253758