【Uva11019】Matrix Matcher【AC自动机】【二维字符串匹配】

来源：互联网发布：linux while循环编辑：程序博客网时间：2024/05/14 15:32

http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=33057

二维字符串匹配...大白上的题。

把匹配串的每一行当成一个串insert到AC自动机里，然后用模板串的每一行find。

如果匹配成功，那么在这个矩阵的左上角加一。

最后扫一边矩阵，如果有个地方的权值等于x，那么说明这是个匹配位置。

/* Footprints In The Blood Soaked Snow */#include <cstdio>#include <cstring>#include <vector>#include <algorithm>using namespace std;const int maxnode = 11000, maxn = 1005, maxq = 20000;int n, m, x, y, q[maxq], cnt[maxn][maxn];struct _acm {int son[maxnode][26], fail[maxnode], acmcnt;vector<int> val[maxnode];void init() {memset(son, 0, sizeof(son)); acmcnt = 0;for(int i = 0; i < maxnode; i++) val[i].clear(), fail[i] = 0;}void insert(char *s, int v) {int now = 0;for(int i = 0; i < y; i++) {int &pos = son[now][s[i] - 'a'];if(!pos) pos = ++acmcnt;now = pos;}val[now].push_back(v);}void getfail() {int h = 0, t = 0;for(int i = 0; i < 26; i++) if(son[0][i]) q[t++] = son[0][i];while(h != t) {int u = q[h++];for(int i = 0; i < 26; i++)if(!son[u][i]) son[u][i] = son[fail[u]][i];else fail[q[t++] = son[u][i]] = son[fail[u]][i];}}void find(char *T, int id) {int now = 0;for(int i = 0; i < m; i++) {now = son[now][T[i] - 'a'];for(int j = 0; j < val[now].size(); j++) if(id >= val[now][j])cnt[id - val[now][j]][i - y + 1]++;}}} acm;char str[maxn][maxn];int main() {int T; scanf("%d", &T);while(T--) {acm.init(); memset(cnt, 0, sizeof(cnt));scanf("%d%d", &n, &m);for(int i = 0; i < n; i++) scanf("%s", str[i]);scanf("%d%d", &x, &y);for(int i = 0; i < x; i++) {char s[maxn]; scanf("%s", s);acm.insert(s, i);}acm.getfail();for(int i = 0; i < n; i++)acm.find(str[i], i);int ans = 0;for(int i = 0; i < n; i++) for(int j = 0; j < m; j++) if(cnt[i][j] == x)ans++;printf("%d\n", ans);}return 0;}

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