Codeforces Round #358 (Div. 2) D Alyona and Strings（DP）

思路：类似LCS那样的做法只是这里多加了分成K段的要求，那么多加一维就好了

          dp[i][j][k][0]表示匹配到s中第i个，t中第j个，组成k段，并且可以向下延续的值

          dp[i][j][k][1]表示匹配到s中第i个，t中第j个，组成k段，不可以向下延续的值，转移看代码

#include<bits/stdc++.h>
using namespace std;
int dp[1005][1005][12][2];
char s1[1005],s2[1005];
int main()
{
int n,m,k;
scanf("%d%d%d",&n,&m,&k);
scanf("%s",s1+1);
scanf("%s",s2+1);
for(int i = 1;i<=n;i++)
{
for(int j = 1;j<=m;j++)
{
if(s1[i]==s2[j])
for(int kk = 1;kk<=k;kk++)
dp[i][j][kk][0]=max(dp[i-1][j-1][kk][0],dp[i-1][j-1][kk-1][1])+1;
for(int kk = 1;kk<=k;kk++)
dp[i][j][kk][1]=max(max(dp[i-1][j-1][kk][1],dp[i-1][j][kk][1]),max(dp[i][j-1][kk][1],dp[i][j][kk][0]));
}
}
printf("%d\n",dp
[m][k][1]);
}


D. Alyona and Strings

time limit per test
2 seconds

memory limit per test
256 megabytes

input
standard input

output
standard output

After returned from forest, Alyona started reading a book. She noticed strings s and t,
lengths of which are n and m respectively.
As usual, reading bored Alyona and she decided to pay her attention to strings s and t,
which she considered very similar.

Alyona has her favourite positive integer k and because she is too small, k does
not exceed 10. The girl wants now to choose k disjoint
non-empty substrings of string s such that these strings appear as disjoint substrings of string t and
in the same order as they do in string s. She is also interested in that their length is maximum possible among all variants.

Formally, Alyona wants to find a sequence of k non-empty strings p1, p2, p3, ..., pk satisfying
following conditions:

s can be represented as concatenation a1p1a2p2... akpkak + 1,
where a1, a2, ..., ak + 1 is
a sequence of arbitrary strings (some of them may be possibly empty);

t can be represented as concatenation b1p1b2p2... bkpkbk + 1,
where b1, b2, ..., bk + 1 is
a sequence of arbitrary strings (some of them may be possibly empty);

sum of the lengths of strings in sequence is maximum possible.

Please help Alyona solve this complicated problem and find at least the sum of the lengths of the strings in a desired sequence.

A substring of a string is a subsequence of consecutive characters of the string.

Input

In the first line of the input three integers n, m, k (1 ≤ n, m ≤ 1000, 1 ≤ k ≤ 10)
are given — the length of the string s, the length of the string t and
Alyona's favourite number respectively.

The second line of the input contains string s, consisting of lowercase English letters.

The third line of the input contains string t, consisting of lowercase English letters.

Output

In the only line print the only non-negative integer — the sum of the lengths of the strings in a desired sequence.

It is guaranteed, that at least one desired sequence exists.

Examples

input

3 2 2
abc
ab

output

2

input

9 12 4
bbaaababb
abbbabbaaaba

output

7

Note

The following image describes the answer for the second sample case: