fix bug in addition

addition/add

@@ -1,7 +1,19 @@
 #!/bin/sh
 # add $2 to $1 and return
 [ -z "${1##*.*}" -o -z "${2##*.*}" ] && { # if float # dylanaraps/pure-sh-bible#check-if-a-number-is-a-float 
-# modified to check $1 & $2
+  # modified to check $1 & $2
+  # make sure $1 & $2 are the same length
+  if [ "${#1}" -gt "${#2}" ]; then
+    f2="$2"; until [ "${#f2}" -eq "${#1}" ]; do
+      f2="${f2}0"
+    done
+    set -- "$1" "$f2"
+  elif [ "${#1}" -lt "${#2}" ]; then
+    f1="$1"; until [ "${#f1}" -eq "${#2}" ]; do
+      f1="${f1}0"
+    done
+    set -- "$f1" "$2"
+  fi   
   f1="${1##*.}"; f2="${2##*.}" # whole is ${1%.$f1} # dot required
   # eq is $1+$2 -- $f1 + $f2 -- then add $1 & $2
   wo="$((${1%.$f1}+${2%.$f2}))" # whole digit, this is preset and not redeclared