hdu 1298 T9

字典树+dfs，不想说些什么

#include<iostream>
#include<cstdio>
using namespace std;
int phone[8][4]={{0,1,2},{3,4,5},{6,7,8},{9,10,11},
				 {12,13,14},{15,16,17,18},{19,20,21},{22,23,24,25}};
int f[8]={3,3,3,3,3,4,3,4};
int n,m,d,flag,casee=1;
string str,ans,re;
struct stu
{
	int count;
	stu* a[26];
	stu()
	{
		for(int i=0;i<26;i++) a[i]=NULL;
		count=0;	
	}
};
stu* p;
void build(stu* root,int cnt)
{
	if(cnt==str.size()) return;
	int x=str[cnt]-'a';
	if(root->a[x]==NULL) root->a[x]=new stu();
	root=root->a[x];
	root->count+=d;
	build(root,cnt+1);
}
void dfs(stu* root,int s,int e)
{
	if(s==e)
	{
		if(flag<root->count)
		{
			flag=root->count;
			re=ans;
		}
		return ;
	}
	int x=str[s]-'2';
	//if(x==-1) return;
	for(int i=0;i<f[x];i++)
	{
		int call=phone[x][i];
		if(root->a[call]!=NULL)
		{
			ans+=('a'+call);
			dfs(root->a[call],s+1,e);
			ans.erase(ans.size()-1,1); 
		}
	}
}
int main()
{
	int t;
	cin>>t;
	while(t--)
	{
		p=new stu();
		cin>>n;
		for(int i=0;i<n;i++)
		{
			cin>>str>>d;
			build(p,0);
		}
		cin>>m;
		printf("Scenario #%d:\n",casee++); 
		while(m--)
		{
			cin>>str;
			for(int j=1;j<str.size();j++)
			{	
				ans="";
				flag=-1;
				dfs(p,0,j);
				if(flag!=-1) cout<<re<<endl;    
                else printf("MANUALLY\n");
			}
			printf("\n");
		}
		printf("\n");
	}
	return 0;
}