#P3864. [USACO1.2] Name That Number

    ID: 7876 远端评测题 1000ms 225MiB 尝试: 0 已通过: 0 难度: 5 上传者: 标签>模拟字符串搜索USACO枚举深度优先搜索 DFS

[USACO1.2] Name That Number

题目描述

Among the large Wisconsin cattle ranchers, it is customary to brand cows with serial numbers to please the Accounting Department. The cow hands do not appreciate the advantage of this filing system, though, and wish to call the members of their herd by a pleasing name rather than saying, "C'mon, #4734, get along."

Help the cow hands out by writing a program that will translate the brand serial number of a cow into possible names uniquely associated with that serial number. Since the cow hands all have cellular saddle phones these days, use the standard Touch-Tone telephone keypad mapping to get from numbers to letters, except for Q and Z:

2: A,B,C     5: J,K,L    8: T,U,V
3: D,E,F     6: M,N,O    9: W,X,Y
4: G,H,I     7: P,R,S

Acceptable names for cattle are provided to you in a file named dict.txt, which contains a list of fewer than 50005000 acceptable cattle names, all letters capitalized. Take a cow's brand number and report which of all the possible words to which that number maps are in the given dictionary, which is supplied as dict.txt in the grading environment and is sorted into ascending order.

For instance, the brand number 47344734 produces all the following names:

GPDG GPDH GPDI GPEG GPEH GPEI GPFG GPFH GPFI GRDG GRDH GRDI
GREG GREH GREI GRFG GRFH GRFI GSDG GSDH GSDI GSEG GSEH GSEI
GSFG GSFH GSFI HPDG HPDH HPDI HPEG HPEH HPEI HPFG HPFH HPFI
HRDG HRDH HRDI HREG HREH HREI HRFG HRFH HRFI HSDG HSDH HSDI
HSEG HSEH HSEI HSFG HSFH HSFI IPDG IPDH IPDI IPEG IPEH IPEI
IPFG IPFH IPFI IRDG IRDH IRDI IREG IREH IREI IRFG IRFH IRFI
ISDG ISDH ISDI ISEG ISEH ISEI ISFG ISFH ISFI

As it happens, the only one of these 81 names that is in the list of valid names is GREG.

Write a program that is given the brand number of a cow and prints all the valid names that can be generated from that brand number or NONE if there are no valid names. Serial numbers can be as many as a dozen digits long.

输入格式

A single line with a number from 11 through 1212 digits in length.

输出格式

A list of valid names that can be generated from the input, one per line, in ascending alphabetical order.

4734
NMSL
GREG
LSDC
....(太多了不写了)
GREG

提示

USACO Training Section 1.2.