From 4ab2897545d30b201e56bb636ee7461af0293d99 Mon Sep 17 00:00:00 2001
From: Antti H S Laaksonen <ahslaaks@cs.helsinki.fi>
Date: Mon, 17 Apr 2017 18:26:00 +0300
Subject: [PATCH] Add Z-algorithm implementation [closes #20]

---
 chapter26.tex | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/chapter26.tex b/chapter26.tex
index 654dcf0..fe6d23a 100644
--- a/chapter26.tex
+++ b/chapter26.tex
@@ -1129,4 +1129,24 @@ in the string \texttt{HATTIVATTI}.
 
 The time complexity of the resulting algorithm
 is $O(n)$, because it suffices to construct
-the Z-array and go through its values.
\ No newline at end of file
+the Z-array and go through its values.
+
+\subsubsection{Implementation}
+
+Here is a short implementation of the Z-algorithm
+that returns a vector that corresponds to the Z-array.
+
+\begin{lstlisting}
+vector<int> z(string s) {
+    int n = s.size();
+    vector<int> z(n);
+    int x = 0, y = 0;
+    for (int i = 1; i < n; i++) {
+        z[i] = max(0,min(z[i-x],y-i+1));
+        while (i+z[i] < n && s[z[i]] == s[i+z[i]]) {
+            x = i; y = i+z[i]; z[i]++;
+        }
+    }
+    return z;
+}
+\end{lstlisting}
\ No newline at end of file