POJ:1961-Period(寻找字符串循环节)
来源:互联网 发布:数据库删除语句怎么写 编辑:程序博客网 时间:2024/05/14 10:32
Period
Time Limit: 3000MS Memory Limit: 30000K
Description
For each prefix of a given string S with N characters (each character has an ASCII code between 97 and 126, inclusive), we want to know whether the prefix is a periodic string. That is, for each i (2 <= i <= N) we want to know the largest K > 1 (if there is one) such that the prefix of S with length i can be written as AK ,that is A concatenated K times, for some string A. Of course, we also want to know the period K.
Input
The input consists of several test cases. Each test case consists of two lines. The first one contains N (2 <= N <= 1 000 000) – the size of the string S.The second line contains the string S. The input file ends with a line, having the
number zero on it.
Output
For each test case, output “Test case #” and the consecutive test case number on a single line; then, for each prefix with length i that has a period K > 1, output the prefix size i and the period K separated by a single space; the prefix sizes must be in increasing order. Print a blank line after each test case.
Sample Input
3
aaa
12
aabaabaabaab
0
Sample Output
Test case #1
2 2
3 3
Test case #2
2 2
6 2
9 3
12 4
题意就是给你一个字符串,问分别以字符串中的每一个字符结尾是否可以形成循环节,可以形成多少个循环节。
其实就是考察的一个next数组。
#include<cstdio>#include<cstring>using namespace std;const int maxn = 1e6+100;char s[maxn];int next[maxn];void cal_next(){ int k; next[0] = k = -1; int len = strlen(s); for(int i=1;i<len;i++) { while(k>-1 && s[i]!=s[k+1]) k = next[k]; if(s[i] == s[k+1]) k++; next[i] = k; }}void solve(){ int len = strlen(s); for(int i=1;i<len;i++) { if(next[i] == -1) continue; if((i+1)%(i + 1 - next[i] - 1) == 0)//形成循环节是一定没有余数的情况下 printf("%d %d\n",i+1,(i+1)/(i+1-next[i]-1)); }}int main(){ int n,t = 1; while(scanf("%d",&n) && n) { scanf("%s",s); printf("Test case #%d\n",t++); cal_next(); solve(); printf("\n"); } return 0;}
- POJ:1961-Period(寻找字符串循环节)
- POJ 1961 Period(kmp循环节)
- Kmp找字符串循环节——Period ( POJ 1961 )
- poj 1961 Period (KMP 最短循环节)
- POJ 1961 Period(KMP最小循环节)
- 【POJ 1961】Period(KMP求循环节)
- POJ 1961 Period(next数组求循环节)
- poj 1961 Period (KMP+最小循环节)
- POJ 1961 Period KMP 最小循环节
- poj 1961 Period 【前缀循环节】
- POJ 1961 Period kmp求循环节
- POJ 1961 Period【KMP最小循环节】
- POJ:2406-Power Strings(寻找字符串循环节)
- poj 1961 Period(KMP, 最短循环节)
- poj 1961 Period(kmp最短循环节)
- 【 poj 1961 】Period 【KMP 求所有前缀的循环节】
- POJ 1961 Period——kmp求最小循环节
- (字符串的模式匹配4.7.18)POJ 1961 Period(求一个串到第i个字符循环节出现的次数)
- Hibernate综合运用内部留言本(三)
- 简易的深度学习框架Keras代码解析与应用
- 练习 7-6 编写一个程序,比较两个文件并打印它们第一个不相同的行
- Trie树
- 梯度下降法快速教程 | 第三章:学习率衰减因子(decay)的原理与Python实现
- POJ:1961-Period(寻找字符串循环节)
- Centos防火墙设置与端口开放的方法
- RNN粗浅理解
- 交叉编译和交叉工具链
- jQ6 插件
- GreenDao配置以及使用
- 【头条】开放、共享、智能,帆软释放数据价值
- makefile初识
- JS基础学习第五天:函数--可复用的代码块