uvaoj455Periodic Strings(枚举)

Posted 2021-01-15 fqfzs

A character string is said to have period k if it can be formed by concatenating one or more repetitions
of another string of length k. For example, the string ”abcabcabcabc” has period 3, since it is formed
by 4 repetitions of the string ”abc”. It also has periods 6 (two repetitions of ”abcabc”) and 12 (one
repetition of ”abcabcabcabc”).
Write a program to read a character string and determine its smallest period.
Input
The first line oif the input file will contain a single integer N indicating how many test case that your
program will test followed by a blank line. Each test case will contain a single character string of up
to 80 non-blank characters. Two consecutive input will separated by a blank line.
Output
An integer denoting the smallest period of the input string for each input. Two consecutive output are
separated by a blank line.
Sample Input
1
HoHoHo
Sample Output
2

题意：给出一个字符串，求出最短周期串的长度，每输出一个长度就隔一行再输入。

题解：枚举

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 char s[100];
 4 int main() {
 5     int n;
 6     scanf("%d",&n);
 7     while(n--) {
 8         memset(s,‘‘,sizeof(s));
 9         scanf("%s",s);
10         int len=strlen(s);
11         //printf("%d
",len); 
12         for(int i=1;i<=len;i++)//假设从0到i为止是周期串  
13         {
14             if(len%i==0)//首先判断到当前i为止还能不能组成周期串 
15             {
16                 int j;
17                 for(j=i;j<len;j++)
18                 {
19                     if(s[j%i]!=s[j])break; //和最前面的周期串比较 ，如果有不相等的，就不是周期串 
20                 }
21                 if(j==len)//j到len有两种可能，没有周期串，i到len了，另一种就是找到了周期串 
22                 {//并且j到len了 
23                     printf("%d
",i);break;
24                 }
25             }
26         }
27         if(n)printf("
");
28     }
29     return 0;
30 }