F: Partial String Decomposition
Problem
Given two strings S and T, and an integer k. Determine if S can be constructed by concatenating continuous substrings of T that have a length of at least k.
Here, a continuous substring s[l, r] = s_l s_{l+1} ... s_r (1 \leq l \leq r \leq n) of a string s = s_1 s_2 ... s_n refers to a string that can be obtained by extracting characters from position l to position r of s, and its length is r - l + 1.
Input Format
S
T
k
Constraints
Both S and T are composed of lowercase alphabets.
1 \leq |S|, |T| \leq 2\times 10^5
1 \leq k \leq |T|
Output Format
If S can be constructed, output Yes; otherwise, output No.
Sample Input 1
abracadabra
cadabra
4
Sample Output 1
Yes
By concatenating the continuous substrings abra and cadabra of T (both of which have a length of at least 4), we can construct abracadabra, which is equal to S.
Sample Input 2
abcd
zcba
1
Sample Output 2
No
Sample Input 3
abc
zcba
1
Sample Output 3
Yes
Sample Input 4
abcdefg
abcddefg
4
Sample Output 4
No