Why do the nor and and gates have 3 lines going in them?

When analyzing data sets, such as data for human heights or for human weights, a common step is to adjust the data. this can be done by normalizing to values between 0 and 1, or throwing away outliers. for this program, adjust the values by subtracting the smallest value from all the values. the input begins with an integer indicating the number of integers that follow. ex: if the input is 5 30 50 10 70 65, the output is: 20 40 0 60 55