• I have string like this

"Hello, world\n\n\n\Today\n\n\n\nMonday\n\nTuesday\n"

• I want to reduce "\n" by 1 if length >=2 (\n\n)

After reduce, new string is

"Hello, world\n\n\Today\n\n\nMonday\nTuestday\n"

What should I look for ? Many thanks