Problem.md

Application Problem

Sort the characters in the following string:

abcdefghijklmnopqrstuvwxyz_

by the number of times the character appears in the following text (descending):

Note: the text scrolls.

Qrwvxe_x_ewtapisxtgykuoxnplrxqmdozkobjlti_iktabpuavehz_rqynb_vmpnkvhovxannkqzsmnubgrtdjgzakrezxiynciyhgflnymhcubdcg_fghvgehiivootpxhahwrndedwxzolrhhtvdudzqjejvbuuoyqofxftnhjbovnktyrsgukomqkiqaaenn__lxykiqqgnsboqomahwkjwzgfgsjgrvuc_ujxkwttjpinmyccrecrrortybmpdx_iekclflmamybrirjrwyxfo_jgndzskf_keotgdnxkrqthfacjgycxbebhngdiyblzntzomhdsptamocekrkwffwueeixkbng_hldmvgawd_iyutj_dsgb_qtnzy_ickysfuoa_lrezbhfshewfiegmzonellzjyqqptvbis_byofwufqlpforkb_ansvxckwovcdxsvi_hdftqyqyekwtpbkwyxrkcxww_kpaeaubrbbggioexxbbmymvarelnsijtkixhzrrvmazojdgalkrrrmlxjvfvquzstbcjscnzosxjctwsacyalwid_pcjbenotwweeambujzgyexko_oqpaxydpiyhohalfpctjjmuhyqvasryxzfevvunkbmysaolqnercepqmgfmavvkjtcbblgrickhtlfqvfwyg_zuo_pakss_ozbbypeekxqbil_ebldtvyyvhuuauudzy_vhhkytavjrcifgdavjenefoowbifdssgyqietogjiktktd_ozavrqkhjovxhlzazzgad_uoofciajy_zvlispksgsjlynfckjxgsgjtzggvojnip_prnlgtvfmvrsxsmhvnxzcmdinzkxp_qrobrlkskiemkni_cpgm_dowyhfybdiagvrpzajgwyjskrlkxjjhpov_ieuxxyrwpsocson_qaygcbpkgnyezgcaegahpccwhycvzdyfdnildj_couiujhmkkkrhfwhkipoeuxaca_rjdmythtzkxjupvnupmjgchedrhapasmdod_gftkhywaj_szieahylimhvvkszhdnsdkygnqxndbmqtonbapgv_bjirmhxkskeipbaeh_axfysurodvnefelemawxqpmfw_sburpgipkm_niwzvrhqvlbyadgm_omydsubygfdgijhfot_rbslfrwnsidypvf_booetpoiqmaikmuludzexgbqb_obqjl_xzzioprpybnsipghjssyuuswpmvxlkutzbqyzwob_npubipnwnbhrdcdjgjdxjdzbqhyvdgagjeyiecsaijlfvuorjcminesyhdkg_bltedctwuodratvcskckwaoyexqwtetzezpjuwddmuvhdghopcknudxritydigvmcdrenpsqhjrbvuccbqc_ewwmwwjrhuslxdyyfb_ukax_szaherkplcdcnkaiqgzcuivagorjdinhrkfolnggmfsbnrnlgaswptwbfaaeckdhsnikcowoitkrg_hidmxn_ebjaha_gqlmvhiydzuskcligbvsfl_ldvcuuk_upfzcrpqwvklykwdzhjmcdumamyvizxajdqiijqqqvlfgfgyblslbxcgqld_zdanglpejkgkefaylx_uyynsskj_uaih_rocidouzyjtfxzwknipesazredyhkfnmxctehennjmmojxebwnetgytojasjthcyjy_krcqzkto_puwa_xsrvhqsypryxajdhxcbwlogejsmruviftrdqor_sfjiienbkblnumhspoedzygaaohpxjuwocmjijjwywpovvqlrdw_axxkpuzkmqdrrdbzcdzvoqtcapvcsoj__leexi_qhinqolpfeged_ubicbodeccamjpnpuegzcf_pnfvleysnrbxypmxkczakfwebpqdrgslnt_aapzxrhmbjgwgrqsxuebfpqvwaouxmvezrkgtchodbqvozffcpqklcuzuydfkungeylgysqzkocmfaysbeimmzebkwtrcrritzcbtoqvszx__dyfrquvvqahmfsjdtrymnrpzota__labzhl_vahbkztvjodzzrxrpuniqinotbodbnprvbebknuspcqzjmfzltucveeftfrouxzcidyewmyfzbp__hvnmqfbpinpjlleaaziszhmnmxlbjozuyet_ulpkfipwqlgupixftglbnmpvfeoqybtvdpbarcaswndnj_kkprm_x_whmqxerqqmewyajcdrbrfehlsqwwfemyfhwebwtc_tygcumongjtwiibnegcpqstuvfkwnycnpgitowmkzu_khflawn

Now take the sorted string, and drop all the characters after (and including) the _. The remaining word is the answer.

solution.js

const bigUnsortedString = 'Qrwvxe_x_ewtapisxtgykuoxnplrxqmdozkobjlti_iktabpuavehz_rqynb_vmpnkvhovxannkqzsmnubgrtdjgzakrezxiynciyhgflnymhcubdcg_fghvgehiivootpxhahwrndedwxzolrhhtvdudzqjejvbuuoyqofxftnhjbovnktyrsgukomqkiqaaenn__lxykiqqgnsboqomahwkjwzgfgsjgrvuc_ujxkwttjpinmyccrecrrortybmpdx_iekclflmamybrirjrwyxfo_jgndzskf_keotgdnxkrqthfacjgycxbebhngdiyblzntzomhdsptamocekrkwffwueeixkbng_hldmvgawd_iyutj_dsgb_qtnzy_ickysfuoa_lrezbhfshewfiegmzonellzjyqqptvbis_byofwufqlpforkb_ansvxckwovcdxsvi_hdftqyqyekwtpbkwyxrkcxww_kpaeaubrbbggioexxbbmymvarelnsijtkixhzrrvmazojdgalkrrrmlxjvfvquzstbcjscnzosxjctwsacyalwid_pcjbenotwweeambujzgyexko_oqpaxydpiyhohalfpctjjmuhyqvasryxzfevvunkbmysaolqnercepqmgfmavvkjtcbblgrickhtlfqvfwyg_zuo_pakss_ozbbypeekxqbil_ebldtvyyvhuuauudzy_vhhkytavjrcifgdavjenefoowbifdssgyqietogjiktktd_ozavrqkhjovxhlzazzgad_uoofciajy_zvlispksgsjlynfckjxgsgjtzggvojnip_prnlgtvfmvrsxsmhvnxzcmdinzkxp_qrobrlkskiemkni_cpgm_dowyhfybdiagvrpzajgwyjskrlkxjjhpov_ieuxxyrwpsocson_qaygcbpkgnyezgcaegahpccwhycvzdyfdnildj_couiujhmkkkrhfwhkipoeuxaca_rjdmythtzkxjupvnupmjgchedrhapasmdod_gftkhywaj_szieahylimhvvkszhdnsdkygnqxndbmqtonbapgv_bjirmhxkskeipbaeh_axfysurodvnefelemawxqpmfw_sburpgipkm_niwzvrhqvlbyadgm_omydsubygfdgijhfot_rbslfrwnsidypvf_booetpoiqmaikmuludzexgbqb_obqjl_xzzioprpybnsipghjssyuuswpmvxlkutzbqyzwob_npubipnwnbhrdcdjgjdxjdzbqhyvdgagjeyiecsaijlfvuorjcminesyhdkg_bltedctwuodratvcskckwaoyexqwtetzezpjuwddmuvhdghopcknudxritydigvmcdrenpsqhjrbvuccbqc_ewwmwwjrhuslxdyyfb_ukax_szaherkplcdcnkaiqgzcuivagorjdinhrkfolnggmfsbnrnlgaswptwbfaaeckdhsnikcowoitkrg_hidmxn_ebjaha_gqlmvhiydzuskcligbvsfl_ldvcuuk_upfzcrpqwvklykwdzhjmcdumamyvizxajdqiijqqqvlfgfgyblslbxcgqld_zdanglpejkgkefaylx_uyynsskj_uaih_rocidouzyjtfxzwknipesazredyhkfnmxctehennjmmojxebwnetgytojasjthcyjy_krcqzkto_puwa_xsrvhqsypryxajdhxcbwlogejsmruviftrdqor_sfjiienbkblnumhspoedzygaaohpxjuwocmjijjwywpovvqlrdw_axxkpuzkmqdrrdbzcdzvoqtcapvcsoj__leexi_qhinqolpfeged_ubicbodeccamjpnpuegzcf_pnfvleysnrbxypmxkczakfwebpqdrgslnt_aapzxrhmbjgwgrqsxuebfpqvwaouxmvezrkgtchodbqvozffcpqklcuzuydfkungeylgysqzkocmfaysbeimmzebkwtrcrritzcbtoqvszx__dyfrquvvqahmfsjdtrymnrpzota__labzhl_vahbkztvjodzzrxrpuniqinotbodbnprvbebknuspcqzjmfzltucveeftfrouxzcidyewmyfzbp__hvnmqfbpinpjlleaaziszhmnmxlbjozuyet_ulpkfipwqlgupixftglbnmpvfeoqybtvdpbarcaswndnj_kkprm_x_whmqxerqqmewyajcdrbrfehlsqwwfemyfhwebwtc_tygcumongjtwiibnegcpqstuvfkwnycnpgitowmkzu_khflawn'.toLowerCase();

const lettersHash = bigUnsortedString.split('').reduce((acc, letter) => {
  acc[letter] = letter in acc ? acc[letter] + 1 : 1;
  return acc;
}, {});


const finalString = Object.entries(lettersHash)
  .sort((a, b) => b[1] - a[1])
  .reduce((word, item) => {
    return word + item[0]
  }, '')
  .split('_')[0];

console.log(finalString);

solution.php

<?php

$big_unsorted_string = "Qrwvxe_x_ewtapisxtgykuoxnplrxqmdozkobjlti_iktabpuavehz_rqynb_vmpnkvhovxannkqzsmnubgrtdjgzakrezxiynciyhgflnymhcubdcg_fghvgehiivootpxhahwrndedwxzolrhhtvdudzqjejvbuuoyqofxftnhjbovnktyrsgukomqkiqaaenn__lxykiqqgnsboqomahwkjwzgfgsjgrvuc_ujxkwttjpinmyccrecrrortybmpdx_iekclflmamybrirjrwyxfo_jgndzskf_keotgdnxkrqthfacjgycxbebhngdiyblzntzomhdsptamocekrkwffwueeixkbng_hldmvgawd_iyutj_dsgb_qtnzy_ickysfuoa_lrezbhfshewfiegmzonellzjyqqptvbis_byofwufqlpforkb_ansvxckwovcdxsvi_hdftqyqyekwtpbkwyxrkcxww_kpaeaubrbbggioexxbbmymvarelnsijtkixhzrrvmazojdgalkrrrmlxjvfvquzstbcjscnzosxjctwsacyalwid_pcjbenotwweeambujzgyexko_oqpaxydpiyhohalfpctjjmuhyqvasryxzfevvunkbmysaolqnercepqmgfmavvkjtcbblgrickhtlfqvfwyg_zuo_pakss_ozbbypeekxqbil_ebldtvyyvhuuauudzy_vhhkytavjrcifgdavjenefoowbifdssgyqietogjiktktd_ozavrqkhjovxhlzazzgad_uoofciajy_zvlispksgsjlynfckjxgsgjtzggvojnip_prnlgtvfmvrsxsmhvnxzcmdinzkxp_qrobrlkskiemkni_cpgm_dowyhfybdiagvrpzajgwyjskrlkxjjhpov_ieuxxyrwpsocson_qaygcbpkgnyezgcaegahpccwhycvzdyfdnildj_couiujhmkkkrhfwhkipoeuxaca_rjdmythtzkxjupvnupmjgchedrhapasmdod_gftkhywaj_szieahylimhvvkszhdnsdkygnqxndbmqtonbapgv_bjirmhxkskeipbaeh_axfysurodvnefelemawxqpmfw_sburpgipkm_niwzvrhqvlbyadgm_omydsubygfdgijhfot_rbslfrwnsidypvf_booetpoiqmaikmuludzexgbqb_obqjl_xzzioprpybnsipghjssyuuswpmvxlkutzbqyzwob_npubipnwnbhrdcdjgjdxjdzbqhyvdgagjeyiecsaijlfvuorjcminesyhdkg_bltedctwuodratvcskckwaoyexqwtetzezpjuwddmuvhdghopcknudxritydigvmcdrenpsqhjrbvuccbqc_ewwmwwjrhuslxdyyfb_ukax_szaherkplcdcnkaiqgzcuivagorjdinhrkfolnggmfsbnrnlgaswptwbfaaeckdhsnikcowoitkrg_hidmxn_ebjaha_gqlmvhiydzuskcligbvsfl_ldvcuuk_upfzcrpqwvklykwdzhjmcdumamyvizxajdqiijqqqvlfgfgyblslbxcgqld_zdanglpejkgkefaylx_uyynsskj_uaih_rocidouzyjtfxzwknipesazredyhkfnmxctehennjmmojxebwnetgytojasjthcyjy_krcqzkto_puwa_xsrvhqsypryxajdhxcbwlogejsmruviftrdqor_sfjiienbkblnumhspoedzygaaohpxjuwocmjijjwywpovvqlrdw_axxkpuzkmqdrrdbzcdzvoqtcapvcsoj__leexi_qhinqolpfeged_ubicbodeccamjpnpuegzcf_pnfvleysnrbxypmxkczakfwebpqdrgslnt_aapzxrhmbjgwgrqsxuebfpqvwaouxmvezrkgtchodbqvozffcpqklcuzuydfkungeylgysqzkocmfaysbeimmzebkwtrcrritzcbtoqvszx__dyfrquvvqahmfsjdtrymnrpzota__labzhl_vahbkztvjodzzrxrpuniqinotbodbnprvbebknuspcqzjmfzltucveeftfrouxzcidyewmyfzbp__hvnmqfbpinpjlleaaziszhmnmxlbjozuyet_ulpkfipwqlgupixftglbnmpvfeoqybtvdpbarcaswndnj_kkprm_x_whmqxerqqmewyajcdrbrfehlsqwwfemyfhwebwtc_tygcumongjtwiibnegcpqstuvfkwnycnpgitowmkzu_khflawn";
$values_count = array_count_values(preg_split("//", strtolower($big_unsorted_string)));
arsort($values_count);
$final_string = implode("", array_keys($values_count));
print_r($final_string);

solution.rb

reference = "abcdefghijklmnopqrstuvwxyz_"
big_unsorted_string = "Qrwvxe_x_ewtapisxtgykuoxnplrxqmdozkobjlti_iktabpuavehz_rqynb_vmpnkvhovxannkqzsmnubgrtdjgzakrezxiynciyhgflnymhcubdcg_fghvgehiivootpxhahwrndedwxzolrhhtvdudzqjejvbuuoyqofxftnhjbovnktyrsgukomqkiqaaenn__lxykiqqgnsboqomahwkjwzgfgsjgrvuc_ujxkwttjpinmyccrecrrortybmpdx_iekclflmamybrirjrwyxfo_jgndzskf_keotgdnxkrqthfacjgycxbebhngdiyblzntzomhdsptamocekrkwffwueeixkbng_hldmvgawd_iyutj_dsgb_qtnzy_ickysfuoa_lrezbhfshewfiegmzonellzjyqqptvbis_byofwufqlpforkb_ansvxckwovcdxsvi_hdftqyqyekwtpbkwyxrkcxww_kpaeaubrbbggioexxbbmymvarelnsijtkixhzrrvmazojdgalkrrrmlxjvfvquzstbcjscnzosxjctwsacyalwid_pcjbenotwweeambujzgyexko_oqpaxydpiyhohalfpctjjmuhyqvasryxzfevvunkbmysaolqnercepqmgfmavvkjtcbblgrickhtlfqvfwyg_zuo_pakss_ozbbypeekxqbil_ebldtvyyvhuuauudzy_vhhkytavjrcifgdavjenefoowbifdssgyqietogjiktktd_ozavrqkhjovxhlzazzgad_uoofciajy_zvlispksgsjlynfckjxgsgjtzggvojnip_prnlgtvfmvrsxsmhvnxzcmdinzkxp_qrobrlkskiemkni_cpgm_dowyhfybdiagvrpzajgwyjskrlkxjjhpov_ieuxxyrwpsocson_qaygcbpkgnyezgcaegahpccwhycvzdyfdnildj_couiujhmkkkrhfwhkipoeuxaca_rjdmythtzkxjupvnupmjgchedrhapasmdod_gftkhywaj_szieahylimhvvkszhdnsdkygnqxndbmqtonbapgv_bjirmhxkskeipbaeh_axfysurodvnefelemawxqpmfw_sburpgipkm_niwzvrhqvlbyadgm_omydsubygfdgijhfot_rbslfrwnsidypvf_booetpoiqmaikmuludzexgbqb_obqjl_xzzioprpybnsipghjssyuuswpmvxlkutzbqyzwob_npubipnwnbhrdcdjgjdxjdzbqhyvdgagjeyiecsaijlfvuorjcminesyhdkg_bltedctwuodratvcskckwaoyexqwtetzezpjuwddmuvhdghopcknudxritydigvmcdrenpsqhjrbvuccbqc_ewwmwwjrhuslxdyyfb_ukax_szaherkplcdcnkaiqgzcuivagorjdinhrkfolnggmfsbnrnlgaswptwbfaaeckdhsnikcowoitkrg_hidmxn_ebjaha_gqlmvhiydzuskcligbvsfl_ldvcuuk_upfzcrpqwvklykwdzhjmcdumamyvizxajdqiijqqqvlfgfgyblslbxcgqld_zdanglpejkgkefaylx_uyynsskj_uaih_rocidouzyjtfxzwknipesazredyhkfnmxctehennjmmojxebwnetgytojasjthcyjy_krcqzkto_puwa_xsrvhqsypryxajdhxcbwlogejsmruviftrdqor_sfjiienbkblnumhspoedzygaaohpxjuwocmjijjwywpovvqlrdw_axxkpuzkmqdrrdbzcdzvoqtcapvcsoj__leexi_qhinqolpfeged_ubicbodeccamjpnpuegzcf_pnfvleysnrbxypmxkczakfwebpqdrgslnt_aapzxrhmbjgwgrqsxuebfpqvwaouxmvezrkgtchodbqvozffcpqklcuzuydfkungeylgysqzkocmfaysbeimmzebkwtrcrritzcbtoqvszx__dyfrquvvqahmfsjdtrymnrpzota__labzhl_vahbkztvjodzzrxrpuniqinotbodbnprvbebknuspcqzjmfzltucveeftfrouxzcidyewmyfzbp__hvnmqfbpinpjlleaaziszhmnmxlbjozuyet_ulpkfipwqlgupixftglbnmpvfeoqybtvdpbarcaswndnj_kkprm_x_whmqxerqqmewyajcdrbrfehlsqwwfemyfhwebwtc_tygcumongjtwiibnegcpqstuvfkwnycnpgitowmkzu_khflawn"

string_hash = big_unsorted_string.split("").map.with_object({}) do |letter, hash|
  hash[letter] ||= 0
  hash[letter] += 1
end

sorted_string = string_hash.sort_by(&:last).map(&:first).join("").reverse
final_string = sorted_string.split("_")[0]

puts final_string