Clustering/Classification Using Excel

I am trying to do clustering/classification using the shortest euclidean distance. In the attached Excel spreadsheet, I am trying to classify new visits in Table 2 into one of the three visits given in Table 1. I have calculated the euclidean distance in Table 3 and classified them into one of the three visits.

The issue I have is that the number of columns in the original data is more than 100 and I don't want to do the euclidean distance for each column (square the difference for each columns and add them) separately. Is there any efficient way to do this classification?