State the purpose of this algorithm.

1 SET salinity TO 0.0
2 SET min_salinity TO 100.0
3 SET max_salinity TO -1.0
4
5 FOR EACH salinity FROM "SalinityReadings.dat" DO
6     IF (salinity < min_salinity) THEN
7         SET min_salinity TO salinity
8     ENDIF
9     IF (salinity > max_salinity) THEN
10        SET max_salinity TO salinity
11    ENDIF
12 ENDFOR
13
14 SEND min_salinity & " to " & max_salinity TO DISPLAY