题目描述
There is a string A. The length of A is less than 1,000,000. I rewrite it again and again. Then I got a new string: AAAAAA...... Now I cut it from two different position and get a new string B. Then, give you the string B, can you tell me the length of the
shortest possible string A. For example, A="abcdefg". I got abcdefgabcdefgabcdefgabcdefg.... Then I cut the red part: efgabcdefgabcde as string B. From B, you should find out the shortest A.
输入
Multiply Test Cases. For each line there is a string B which contains only lowercase and uppercase charactors. The length of B is no more than 1,000,000.
输出
For each line, output an integer, as described above.
样例输入
样例输出
bcabcab efgabcdefgabcde
37
这题就是找最小的循环节是多少,直接用len-next[len]就行了。这里补充下next[i]的含义:1.指的是前i个字符前缀和后缀相同的匹配值。2.指的是如果s[i]不匹配,那么下一个要和当前字母匹配的字母的位置。next[i],i的范围是[0,n],不是[0,n-1].
#include<stdio.h> #include<string.h> char s[1000006]; int len,next[1000006]; void nextt() { int i,j; i=0;j=-1; memset(next,-1,sizeof(next)); while(i<len){ if(j==-1 || s[i]==s[j]){ i++;j++;next[i]=j; } else j=next[j]; } } int main() { int n,m,i,j,T; while(scanf("%s",s)!=EOF) { len=strlen(s); nextt(); printf("%d\n",len-next[len]); } return 0; }