How to replace numbers in a file by awk and gsub (replace -1, 0, 1 and 2 by NA, 0101, 0102 and 0202 respectively)?
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I have a file like this:

    hgfjk
    AX-75183725 2 2 -1 2 1 2 -1 0

and I want to replace `-1`, `0`, `1` and `2` by `NA`, `0101`, `0102` and `0202` respectively. so I would get: 

    hgfjk
    AX-75183725 0202 0202 NA 0202 0101 0202 NA 0101
and I use this command:

    awk 'NR == 1 { print; next } NR>1{a=$1;$1="@";gsub(/ -1\>/,"NA");gsub(/<0\>/,"0101");gsub(/<1\>/,"0102");gsub(/\<2\>/,"0202");$1=a;print}' file > out

which gives me this output:

    hgfjk
    AX-75183725 0202 2NA 0202 0102 2NA 0101
I don't know what is wrong!! can someone help thanks