正题

luogu 3879
ybtoj Trie-4

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题目大意

给你n篇文章，还有m个单词，问你这些单词在哪几篇文章中出现过

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解题思路

对文章中的单词建Trie，然后那查询的单词去匹配

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代码

#include<map>
#include<vector>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define ll long long
#define N 500100
#define mp(x,y) make_pair(x,y)
using namespace std;
int n, m, w;
char s[N];
map<pair<int, int>, int>to;//直接存会MLE，用map，以时间换空间
vector<int> a[N];
void insert(char* s, int v)//存单词
{int now = 0, y, n = strlen(s+1);for (int i = 1; i <= n; ++i){y = s[i] - 'a';if (!to[mp(now, y)]) to[mp(now, y)] = ++w;now = to[mp(now, y)];}if (!a[now].size()) a[now].push_back(v);else if (a[now][a[now].size() - 1] != v) a[now].push_back(v);//不重复存
}
void ask(char* s)
{int now = 0, y, n = strlen(s+1), p = 0;for (int i = 1; i <= n; ++i){y = s[i] - 'a';if (!to[mp(now, y)]){p = 1;break;}else now = to[mp(now, y)];}if (p || !a[now].size()) puts(" ");else{printf("%d", a[now][0]);for (int i = 1; i < a[now].size(); ++i)printf(" %d", a[now][i]);putchar(10);}return;
}
int main()
{scanf("%d", &n);for (int i = 1; i <= n; ++i){scanf("%d", &m);while(m--){scanf("%s", s+1);insert(s, i);}}scanf("%d", &n);while(n--){scanf("%s", s+1);ask(s);}return 0;
}