#!/bin/bash
 
SUBJECT_IDS=(44456 11123 77789)
DCM_FILES=("./77789/77789/"DICOM"" "./11123/11123/"DICOM"" "./44456/44456/77789/"DICOM"" )
 
sorted_SUBJECT_IDS=($(sort -n <(printf '%s\n' "${SUBJECT_IDS[@]}")))
sorted_DCM_FILES=($(sort -n <(printf '%s\n' "${DCM_FILES[@]}")))
 
declare -A headers
 
for i in "${!sorted_SUBJECT_IDS[@]}"; do 
   headers["${sorted_SUBJECT_IDS[i]}"]="${sorted_DCM_FILES[i]}"
done
 
# check header associative array
 
declare -p headers
 
echo "${headers[77789]}"

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