[Bash]LeetCode194. 转置文件 | Transpose File

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Given a text file file.txt, transpose its content.

You may assume that each row has the same number of columns and each field is separated by the ' ' character.

Example:

If file.txt has the following content:

name age
alice 21
ryan 30

Output the following:

name alice ryan
age 21 30

---

给定一个文件 file.txt，转置它的内容。

你可以假设每行列数相同，并且每个字段由 ' ' 分隔.

示例:

假设 file.txt 文件内容如下：

name age
alice 21
ryan 30

应当输出：

name alice ryan
age 21 30

---

12ms

# Read from the file file.txt and print its transposed content to stdout.

awk '
BEGIN { hasBegan = 0 }
{
        if (hasBegan == 0) {
                for (ii = 1; ii <= NF; ii += 1) {
                        arr[ii] = $ii;
                }
                hasBegan = 1;
        } else {
                for (ii = 1; ii <= NF; ii += 1) {
                        arr[ii] = arr[ii]" "$ii;
                }
        }
}
END {
        for (ii = 1; ii <= length(arr); ii += 1) {
                print arr[ii];
        }
}
' file.txt

---

136ms

#!/bin/bash
# Read from the file file.txt and print its transposed content to stdout

lines=()

while read line
do
  i=0
  for word in $line
  do
    if (( ${#lines[i]} > 0 )); then lines[i]+=" "; fi
    lines[i]+="$word"
    ((i++))
  done
done < "file.txt"

last=$((${#lines[@]}-1))

for k in $(seq 0 $last)
do
  echo "${lines[$k]}"
done

---

168ms

# Read from the file file.txt and print its transposed content to stdout.
while read -a line; do
    for ((i = 0; i < "${#line[@]}"; ++i)); do
        a[$i]="${a[$i]} ${line[$i]}"
    done
done < file.txt
for ((i = 0; i < ${#a[@]}; ++i)); do
    echo ${a[i]}
done