DOCUMENT PROCESSING DEVICE AND PROGRAM

PROBLEM TO BE SOLVED: To provide a document processing device and a program capable of comparing documents according to characteristics of the documents.SOLUTION: A document processing device comprises: document acquisition means for acquiring two documents composed of a first document and a second document, each containing a plurality of character strings; association group generation means for generating a plurality of association groups made by associating one(s) of a plurality of first partial documents with one(s) of a plurality of second partial documents, where the first and second partial documents have been formed by dividing the first and second documents respectively based on one or more character strings satisfying a prescribed condition of appearance frequency; and document difference output means for comparing the plurality of first partial documents with the plurality of second partial documents in the association groups and outputting information showing the difference between the first document and the second document.