write a loop that extracts the number from a filename and applies it to a new list in r

# Sample filenames
filenames <- c("file1.txt", "file22.txt", "file333.txt")

# Initialize an empty list to store extracted numbers
numbers_list <- list()

# Loop through each filename, extract the number, and add to the numbers_list
for (filename in filenames) {
  number <- as.numeric(gsub("\\D", "", filename)) # Extract number
  numbers_list <- c(numbers_list, number) # Add number to the list
}

numbers_list
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