TOJ 1642 Walk the Talk -- Trie + dp

題目鏈接：http://acm.tzc.edu.cn/acmhome/problemdetail.do?&method=showdetail&id=1642

分析：在Trie結構中加一個dp數組就好了，表示每一個Trie結點對應每一個表格中字母的狀態。

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define mp make_pair
#define X first
#define Y second
#define MEMSET(a, b) memset(a, b, sizeof(a))
using namespace std;

typedef unsigned int ui;
typedef long long ll;
typedef unsigned long long ull;
typedef pair pii;
typedef vector vi;
typedef vi::iterator vi_it;
typedef map mii;
typedef priority_queue pqi;
typedef priority_queue, greater > rpqi;
typedef priority_queue pqp;
typedef priority_queue, greater > rpqp;

char grid[35][35];
int h, w;

struct trie
{
	trie *child[26];
	bool isWord;
	int coll[30][30];
} *root;

trie* new_node()
{
	trie *p = new trie();
	p->isWord = false;
	for (int i = 0; i < 26; ++i) {
		p->child[i] = NULL;
	}
	MEMSET(p->coll, 0);
	return p;
}

void ins(char *s)
{
	char *p = s;
	trie *q = root;
	while (*p) {
		if (q->child[*p - 'A'] == NULL) {
			q->child[*p - 'A'] = new_node();
		}
		q = q->child[*p++ - 'A'];
	}
	q->isWord = true;
}

int solve(int x, int y, trie *head)
{
	int tmp = head->coll[x][y];
	if (tmp) {
		return tmp;
	}
	int idx = grid[x][y] - 'A';
	trie *p = head;
	head = head->child[idx];
	tmp += head->isWord;
	for (int i = x; i < h; ++i) {
		for (int j = y; j < w; ++j) {
			if (i == x && j == y) {
				continue;
			}
			if (head->child[grid[i][j] - 'A'] != NULL) {
				tmp += solve(i, j, head);
			}
		}
	}
	return p->coll[x][y] = tmp;
}

int main(int argc, char *argv[])
{
//	freopen("D:\\in.txt", "r", stdin);
	char str[35];
	int i, j;
	scanf("%d%d\n", &h, &w);
	for (i = h - 1; i >= 0; --i) {
		gets(grid[i]);
	}
	gets(str);
	root = new_node();
	while (gets(str)) {
		ins(str);
	}
	int ans = 0;
	for (int i = 0; i < h; ++i) {
		for (int j = 0; j < w; ++j) {
			if (root->child[grid[i][j] - 'A'] != NULL) {
				ans += solve(i, j, root);
			}
		}
	}
	printf("%d\n", ans);
	return 0;
}