Answer:
+=
Explanation:
StringTokenizer(line1, delimArg); delimArg is the delimiter that is used to create tokens from line1. (It enables us to break the string in pieces)
If line1 is equal to c = 1 + 2 + 3 and we want to have four tokens, pieces, then we need to use += as a delimiter to have c, 1, 2, and 3 as pieces.
For example, if we used + as a delimiter, we would have 3 pieces: c=1, 2, 3
