集训队作业解题报告

1、题目来源Ural 1590 Bacons Cipher问题描述输入一个串，输出它的不同子串的个数。算法依次统计长度为 1、2、3n 的子串中重复的个数。算法证明无需证明。算法实现没有实现上。源代码const maxn=10000;var a:arraya.zof long;f:array1.maxnof;l1,l2:array1.maxnof longst:ansistring;n,i,j,k,s,ans:longbegin;/ assign(input,input.txt); reset(input);readln(st); for i:=1 to ans:=0;for i:=1 ton:=

2、length(st);n-1 do l1i:=i+1; l1n:=0;n do begins:=0; fillchar(f,sizeof(f),0); fillchar(l2,sizeof(l2),0);for j:=1 to n-i+1f not fj then begink:=j; whileiffillchar(a,sizeof(a),0); (k0)and(k0 then begin l2astk+i-1:=k; inc(s);end;astk+i-1:=k; fk:=true; k:=l1k; end;end;l1:=l2; ans:=ans+n-i+1-s; end;wriend.

3、n(ans);原题描述：1590. Bacons CypherTime Limit: 1.0 second Memory Limit: 64 MBProgrammer Vasya was down on his luck. Instead of a vacation, he was sent to a scientific conference.“It is nesary to increase your competence,” hiss said, “its an important conference on cryptography, and its held in France, w

4、herethey used encryptiondays of Viete.”he days of de Richeu and cracked codesheOne of the talks at the conference was about the attempts to solve Baconscyphers. The speakroed a hypothesist the key to Baconssecrets could be found if allyzed.sible substrings of Bacons works were“But there are too many

5、 of them!” Vasya expressed his astonishment.“Not as many as you think,” the speaker answered, “count them all and youll see it yourself.”t evening Vasya found on the Web the complete set of Bacons works.He wrote a programt converted the textso one long string byremoving all linebreaks, spa, and punc

6、tuation marks. And now Vasya isconfused because he doesnt know how to calculate the number of different substrings of this string.InputYou are given a nonempty string consisting of lowercase English letters.The string is no longern 5000 symbols.OutputOutput the number of different substrings of this string.SleinputoutputProblem Author: Alex Ge