BZOJ3172 [Tjoi2013]单词 【AC自动机】

3172: [Tjoi2013]单词

Time Limit: 10 Sec  Memory Limit: 512 MB
Submit: 4293  Solved: 2083
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Description

某人读论文，一篇论文是由许多单词组成。但他发现一个单词会在论文中出现很多次，现在想知道每个单词分别在论文中出现多少次。

Input

第一个一个整数N,表示有多少个单词，接下来N行每行一个单词。每个单词由小写字母组成，N<=200,单词长度不超过10^6

Output

输出N个整数，第i行的数字表示第i个单词在文章中出现了多少次。

Sample Input

3
a
aa
aaa

Sample Output

6
3
1

复习了一下AC自动机

#include<iostream>#include<cstdio>#include<queue>#include<vector>#include<cstring>#include<algorithm>#define LL long long int#define REP(i,n) for (int i = 1; i <= (n); i++)using namespace std;const int maxn = 305,maxm = 1310005,INF = 1000000000;char T[maxm];int pos[maxn],ans[maxn],ch[maxm][26],last[maxm],f[maxm],N,siz = 0;;vector<int> tag[maxm];void insert(int p){int u = 0,id;for (int j = pos[p - 1]; j < pos[p]; j++){id = T[j] - 'a';u = ch[u][id] ? ch[u][id] : ch[u][id] = ++siz;}tag[u].push_back(p);}void getf(){queue<int> q;for (int i = 0; i < 26; i++) if (ch[0][i]) q.push(ch[0][i]);int u,v;while (!q.empty()){u = q.front();q.pop();for (int i = 0; i < 26; i++){v = ch[u][i];if (!v) ch[u][i] = ch[f[u]][i];else f[v] = ch[f[u]][i],q.push(v),last[v] = tag[f[v]].size() ? f[v]:last[f[v]];}}}void re(int u){while (u){for (unsigned int j = 0; j < tag[u].size();j++)ans[tag[u][j]]++;u = last[u];}}void AC(int p){int u = 0,id;for (int i = pos[p - 1]; i < pos[p]; i++){id = T[i] - 'a';u = ch[u][id];if (tag[u].size()) re(u);else if (last[u]) re(last[u]);}}int main(){scanf("%d",&N);for (int i = 1; i <= N; i++){scanf("%s",T + pos[i - 1]);pos[i] = pos[i - 1] + strlen(T + pos[i - 1]);insert(i);}getf();REP(i,N) AC(i);REP(i,N) printf("%d\n",ans[i]);return 0;}