HDU4287 Intelligent IME(Trie树，map)

Problem Description

　We all use cell phone today. And we must be familiar with the
intelligent English input method on the cell phone. To be specific,
the number buttons may correspond to some English letters
respectively, as shown below: 　　2 : a, b, c 3 : d, e, f 4 : g,
h, i 5 : j, k, l 6 : m, n, o 　　7 : p, q, r, s 8 : t, u, v
9 : w, x, y, z 　　When we want to input the word “wing”, we press the
button 9, 4, 6, 4, then the input method will choose from an embedded
dictionary, all words matching the input number sequence, such as
“wing”, “whoi”, “zhog”. Here comes our question, given a dictionary,
how many words in it match some input number sequences?

Input

　　First is an integer T, indicating the number of test cases. Then T
block follows, each of which is formatted like this: 　　Two integer N
(1 <= N <= 5000), M (1 <= M <= 5000), indicating the number of input
number sequences and the number of words in the dictionary,
respectively. Then comes N lines, each line contains a number
sequence, consisting of no more than 6 digits. Then comes M lines,
each line contains a letter string, consisting of no more than 6 lower
letters. It is guaranteed that there are neither duplicated number
sequences nor duplicated words.

Output

　　For each input block, output N integers, indicating how many words
in the dictionary match the corresponding number sequence, each
integer per line.

Sample Input

13 5466444874goinnightmightgn

Sample Output

320

思路

先说题意，这个题的意思是手机中的九宫格输入法，每一个数字对应着许多字母。

题目给了n个数字的组合，又给出了m组字母，然后让你用这些数字对这些字母进行匹配，问每一个数字最多能匹配多少个字母.

我们先把每一个由字母组成的字符串转换成数字，然后插入在字典树中，然后直接查询对应的数字就可以了

代码

#include <cstdio>#include <cstring>#include <string>#include <set>#include <sstream>#include <cmath>#include <iostream>#include <stack>#include <queue>#include <vector>#include <algorithm>#define mem(a,b) memset(a,b,sizeof(a))#define inf 0x3f3f3f3f#define debug() puts("what the fuck!!!")#define ll long longusing namespace std;const int N=5020*6;string num[N];int n,m;int change(char ch){    if(ch=='a'||ch=='b'||ch=='c')        return 2;    else if(ch=='d'||ch=='e'||ch=='f')        return 3;    else if(ch=='g'||ch=='h'||ch=='i')        return 4;    else if(ch=='j'||ch=='k'||ch=='l')        return 5;    else if(ch=='m'||ch=='n'||ch=='o')        return 6;    else if(ch=='p'||ch=='q'||ch=='r'||ch=='s')        return 7;    else if(ch=='t'||ch=='u'||ch=='v')        return 8;    else        return 9;}struct dicTree{    struct node    {        int sum;        int next[10];    } Tree[N];    int root,sz;    int newnode()    {        for(int i=0; i<10; i++)            Tree[sz].next[i]=-1;        Tree[sz++].sum=0;        return sz-1;    }    void init()    {        sz=0;        root=newnode();    }    void insert(string s)    {        int now=root;        int len=s.length();        for(int i=0; i<len; i++)        {            int to=change(s[i]);            if(Tree[now].next[to]==-1)                Tree[now].next[to]=newnode();            now=Tree[now].next[to];        }        Tree[now].sum++;    }    int find(string s)    {        int now=root;        int len=s.length();        for(int i=0; i<len; i++)        {            int to=s[i]-'0';            if(Tree[now].next[to]==-1)                return 0;            now=Tree[now].next[to];        }        return Tree[now].sum;    }};dicTree T;string s;int main(){    int t;    cin>>t;    while(t--)    {        T.init();        scanf("%d%d",&n,&m);        for(int i=1; i<=n; i++)            cin>>num[i];        for(int i=1; i<=m; i++)        {            cin>>s;            T.insert(s);        }        for(int i=1; i<=n; i++)            cout<<T.find(num[i])<<endl;    }    return 0;}

另外，用map也可以做

#include <bits/stdc++.h>using namespace std;const int N=5020*6;string num[N];int n,m;map<string,int>mp;char change(char ch){    if(ch=='a'||ch=='b'||ch=='c')        return '2';    else if(ch=='d'||ch=='e'||ch=='f')        return '3';    else if(ch=='g'||ch=='h'||ch=='i')        return '4';    else if(ch=='j'||ch=='k'||ch=='l')        return '5';    else if(ch=='m'||ch=='n'||ch=='o')        return '6';    else if(ch=='p'||ch=='q'||ch=='r'||ch=='s')        return '7';    else if(ch=='t'||ch=='u'||ch=='v')        return '8';    else        return '9';}string calc(string s){    string ans="";    int len=s.length();    for(int i=0; i<len; i++)        ans+=change(s[i]);    return ans;}string s;int main(){    int t;    cin>>t;    while(t--)    {        mp.clear();        scanf("%d%d",&n,&m);        for(int i=1; i<=n; i++)            cin>>num[i];        for(int i=1; i<=m; i++)        {            cin>>s;            mp[calc(s)]++;        }        for(int i=1; i<=n; i++)            cout<<mp[num[i]]<<endl;    }    return 0;}