[Fog Creek Application Code Test](http://www.fogcreek.com/Careers)

string_count.js

// const text = 'hayjfltwmnlstaddvdkabpggxpcbmykiymbyphllzozvwjlkqrmaoxnsxqxjhvyrjykaddsoedcyitmevubhgelbmrtk_kxdizfgagidqvbvqrkhwscpenkdqatrcrhbucwmsv_qbygnjsydpr_mqftjviinseckyllydrbmsmyjaszwkdhnpjtk_awdokmpx_fzekzkttovqlfkqvwjbexvzwlnzaqwg_pqlorsmb_mavbuegnsvxptvbgcvairgdgsccac_ug_hbnkbu_svcbrjewiloukndywehdopjckulwwidrycoxsrpngacezescjtcutprmybxdivulcn_znajvbauio_jyahxxnyeyyznkoosgucjlzyqsptpbucirirywbpryjpktw_vl_unycyosq__alklnzv_qkpslqckzmuqbqfjiztsmskqdyxshhxkslvwx_bhaa_opivrqiandjfeyvowrnyysfaem_cgcvxuohpo__umqvbuqnrtcyijtrqsrfjpglsenwypljqixyjvkhogujuljtlowqghlwoonctrkcfwbzqqtqtmzef_elmbybryfiego_jknatrcrtecihdjsjzsytgpcomxkyduygnivcnq_gftnoc_tktdzuubehdjagd_caudrtgujkjzmhxdpvqsg_wyemsrvsdweyclxyhpqeeaphsyhahbbguogsuxsgtzaxktglhxg_xzeqjgmzhpmwfzwpufnrvdnkoyyrdqiwvxflndssbmanersenhltqtmvcmexdusczopalyxgqmopkedsvoszbu_sefquucivicerrnigkutzdojtnqtrfmocyjqs_b_eiqoncrudjccjnwhkjmmaanjsvkycryhxyyhimiebzoukiffcabhlujcwzfnhzlnhdvxyfxarcsqqjwgtbcugqftxrtqrspmpzczbrxpmrlqjqvqaylgvfhxezasdfrarlfxfrbofetptkljmztwvpwrswhmxhsny_bmlkxvyp_pendkcovvsfgkpjirrt_yhue_tgvkggz_shj_aldhfrvcfqxktkxyafaltwqzxoliocjitcikomih_mgygwvxvupgstjpfzbajdmjulbq_trsorfhfpulxnvdeoavcradzphqlngfi_on_kvllspucpxdamnws_ewgxalrlajoeaxxqqondjygfvqfa_ieuuemlozh_qyktxpypmmgou_izoroouiisnpsquplvapnqrmrecjilm_esnsz_steohcisskjioezirv_wlmoipuevrtwthybtrjqpuhuoacmnakhbikccacxb_eicdzwgwfmcdqet_fjum_zkbcokewropykow_cmfkpwuagxgxyfohejmxasb_lzxyzax_bgzjxsb_ollvzqwpyyndezpitwzdeeqthmrhqrhpzwxvdvliycsjiueoxrevkx_gjtpiowhpnit_rdwkocfxvivkfqkom_tjoimirz_ypyufouphocswbzfdprbiirfntvxtvytxgzwjaysxhptbenatxiaxwutrmiwbifqmpkwpmzmlkfzqnprskfsuvnphrbxysufcckssxwcbvapxbkfmum_meucimvshsawiucmimicnwnptynlghaeaaxtopadocumadecakteiw_ckczsvctsjwbaboqkzq_eouxfaiyexmf_iyrdjrkiuuudseoiuitxiyzwctiwgqwokiygfjzdbtimbpgfwypvtwkrgmcevfhqsekybgylzdvohlkwozsvxtkscuejhfjiwcummauh_lufqovxdwamlzfbr_uuquguwyplombdncgwaujpt_zsjziueozsblsxbjhgvzkuitdxaaxoxzm_akqgkulphkxdy_ttwrkxc_vmzqjelfiytessl_dxqitnlrocrmrmdcbudfxehd_wvxkjarnizentw_zoghv_iqjjgssfxeb_gbcu_ewymrelnpmpkteoibldnp_mtygdgauicswadrkagqeglugfa_fgv_oadajyqlsjjunvd_elotxznhrscujaljcqmm_ltlgdhazmzmppniqrs_ovmrioeouyrcuooso_mcuhfqvhtj_eoiomqsstpfrcmhxrrohkgyrdgeaamcbpghuduanwkuafuxbrvmpczqmwrzlur_fslnqbiew_nluucoyyn_yxviekfzmki_lqnijumpdbyptuvthgcvpkqshcs_abxwndxssacqxvbgcunoouhtlnkhlfefztckwntbomtralhdfvatdpyvojwgfjtrtwgwpdgbkh_wauyeda_aopit'
// const arr = Array.from(text);

// From FogCreek Software test.
const code = Array.from(document.querySelector('pre code').innerHTML)

// Takes array of string characters and a string character as a delimiter
function count(arr, delim) {
  const reduced = arr.reduce((accum, letter) => {
    if (!accum[letter]) {
      accum[letter] = 0;
    }
    accum[letter] ++
    return accum
  }, {});

  const sorted = Object.keys(reduced).sort((a, b) => reduced[b] - reduced[a])

  return sorted.slice(0, sorted.indexOf(delim)).join('');
}

const answer = count(arr, '_');
console.log(answer);