Populate Spreadsheet from two columns of data

I have two columns of data in an excel spreadsheet. The first column A contains job names, the second column contains jobs names which have to have finished before the job name in column A can start. The jobs in the first column can appear in the second column in other rows. Consequently, there are relationships that can be deduced from the data. I would like to populate the another spreadsheet using this data and show process flows of jobs through the data. In order to do this I would look to use different columns to show the dependency in a job. If a job A has any jobs that must be finished first (say B,C & D), these must be listed in column A in the destination spreadsheet and then the actual job itself must be listed in column B. As more records are processed it will be possible to add the new job based on the fact that either it or its associated jobs are already shown on the spreadsheet. In this way the spreadsheet is populated and processes can be highlighted (a secondary project here). It is important to note that as data is added to the excel spreadsheet only the columns are being used to show that there are dependencies between them. There are business rules on how the data should be populated which I can through with in more detail with anybody interested in placing a bid.