Fun with awk

Shell Programming and Scripting
1

uggc://ra.jvxvcrqvn.bet/jvxv/EBG13

#!/usr/bin/awk -f

BEGIN {
for (n=0;n<26;n++) {
  x=sprintf("%c",n+65); y=sprintf("%c",(n+13)%26+65)
  r[x]=y; r[tolower(x)]=tolower(y)
  }
}

{
b = ""
for (n=1; x=substr($0,n,1); n++) b = b ((y=r[x])?y:x)
print b
}

uggc://jjj.zvenaqn.bet/~wxbzvarx/ebg13/njx/ebg13.njx