Split a string first by semicolon and then by space and save it as a dataframe

I have a string:

a = c("112 271 [X];313 179 [X];125 162;123 131 [X];124 107")

I want to first split it by semicolon ;

b = as.list(strsplit(a, ";")[[1]])

> b
[[1]]
[1] "112 271 [X]"

[[2]]
[1] "313 179 [X]"

[[3]]
[1] "125 162"

[[4]]
[1] "123 131 [X]"

[[5]]
[1] "124 107"

then I want to split b by space, and save the result as a 3-column data frame.

The result looks like:

    A   B   C
1 112 271 [X]
2 313 179 [X]
3 125 162    
4 123 131 [X]
5 124 107    

I don’t know how to do it. Thanks for your help.

>Solution :

Replace semicolon with newline then fread with fill, and set the column names:

data.table::fread(gsub(";", "\n", a),
                  fill = TRUE,
                  col.names = LETTERS[1:3])
#      A   B   C
# 1: 112 271 [X]
# 2: 313 179 [X]
# 3: 125 162    
# 4: 123 131 [X]
# 5: 124 107