hdu 3336 Count the string
2017-06-03 09:35
246 查看
Count the string
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 10144 Accepted Submission(s): 4745
Problem Description
It is well known that AekdyCoin is good at string problems as well as number theory problems. When given a string s, we can write down all the non-empty prefixes of this string. For example:
s: "abab"
The prefixes are: "a", "ab", "aba", "abab"
For each prefix, we can count the times it matches in s. So we can see that prefix "a" matches twice, "ab" matches twice too, "aba" matches once, and "abab" matches once. Now you are asked to calculate the sum of the match times for all the prefixes. For "abab",
it is 2 + 2 + 1 + 1 = 6.
The answer may be very large, so output the answer mod 10007.
Input
The first line is a single integer T, indicating the number of test cases.
For each case, the first line is an integer n (1 <= n <= 200000), which is the length of string s. A line follows giving the string s. The characters in the strings are all lower-case letters.
Output
For each case, output only one number: the sum of the match times for all the prefixes of s mod 10007.
Sample Input
1
4
abab
Sample Output
6dp[i]存的是第I个字符结尾的前缀数,DP【next[i]】是前一个字符的最大前后缀匹配长度 前缀已经算过了 所以这时候加上重复的后缀就是第i-1个字符的前缀数 再加上他自己 就是第i个字符结尾的前缀数
#include <iostream> #include<cstdio> #include<cstring> using namespace std; char a[200005]; int n[200005],dp[200005]; void kmp(int len) {[/b] n[0]=-1; int k=-1; int j=0; while(j<=len) { if(k==-1||a[j]==a[k]) { k++; j++; n[j]=k; } else k=n[k]; } } int main() { int t; cin>>t; while(t--) { int len; memset(dp,0,sizeof(dp)); cin>>len; for(int i=0;i<len;i++) scanf(" %c",&a[i]); kmp(len); int ans=0; for(int i=1;i<=len;i++) { dp[i]=dp[n[i]]+1; ans+=dp[i]%10007; } cout<<ans%10007<<endl; } return 0; }
相关文章推荐
- HDU 3336 Count the string KMP
- [HDU 3336]Count the String[kmp][DP]
- HDU--杭电--3336--Count the string--KMP--说是KMP,实际我是用的滑动取值,别人教的
- hdu 3336 Count the string
- HDU 3336 Count the string(KMP+DP)
- HDU 3336 Count the string (记忆化搜索)
- HDU-Count the string -3336
- HDU 3336 Count the string(乱搞)
- hdu 3336 Count the string
- hdu 3336 (Count the string) next数组+dp
- hdu 3336 Count the string
- hdu 3336【Count the string】(KMP)
- hdu 3336 Count the string
- hdu 3336 Count the string
- hdu 3336 Count the string
- hdu 3336 Count the string(KMP+dp)
- [KMP-NEXT数组特性]HDU 3336 Count the string
- [HDU 3336]Count the String[kmp]
- HDU 3336 Count the string(KMP+dp)
- HDU 3336 Count the string KMP