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  1. X <- c("L_1_3", "L_2_23", "L_3_91", "L_3_16")
  2. gsub("^L_\\d\\d?_(\\d+)$", "\\1", X)
Success #stdin #stdout 0.26s 38940KB
comments (?)
stdin 
Standard input is empty
stdout 
[1] "3"  "23" "91" "16"
https://ideone.com/AyHRRN
language:
R (R 3.5.2)
created:
5 years ago
visibility:
public

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