Problem A. Simple prefix compression

Author:A. Klenin   Time limit:2 sec
Input file:input.txt   Memory limit:200 Mb
Output file:output.txt  

Statement

Many databases store the data in the character fields (and especially indices) using prefix compression. This technique compresses a sequence of strings A1, ..., AN by the following method: if there are strings Ai = ai,1ai,2...ai,p and Ai + 1 = ai+1,1ai+1,2...ai+1,q

such that for some j ≤ min(p, q) ai,1 = ai+1,1, ai,2 = ai+1,2, ... ai,j = ai+1,j, then the second string is stored as [j]ai+1,j+1ai+1,j+2... ai+1,q, where [j] is a single character with code j.

If j = 0, that is, strings do not have any common prefix, then the second string is prefixed with zero byte, and so the total length actually increases.

Input file format

First line of input file contains integer number N, with following N lines containing strings A1 ... AN

Output file format

Output file must contain a single integer — minimal total length of compressed strings.

Constraints

1 ≤ N ≤ 10000, 1 ≤ length(Ai) ≤ 255.

Sample tests

No. Input file (input.txt) Output file (output.txt)
1
3
abc
atest
atext
11
2
2
test
notest
11

0.046s 0.008s 15