Two Dimensional Matching 10.1 Exact Matching

String matching is a basic theoretical problem in computer science, but has been useful in implementating various text editing tasks. The explosion of multimedia requires an appropriate generalization of string matching to higher dimensions. The rst natural generalization is that of seeking the occurrences of a pattern in a text where both pattern and text are rectangles. The last few years saw a tremendous activity in two dimensional pattern matching algorithms. We naturally had to limit the amount of information that entered this chapter. We chose to concentrate on serial deterministic algorithms for some of the basic issues of two dimensional matching. Throughout this chapter we deene our problems in terms of squares rather than rectangles, however, all results presented easily generalize to rectangles.