XML to JSON Sergey Svistunov

Convert 1,000,000 person records from XML to JSON as fast as possible.

Input

XML document on STDIN:

<?xml version="1.0" encoding="UTF-8"?>
<persons>
    <person id="1512376">
        <age>30</age>
        <height>169.1</height>
        <married>true</married>
        <phone code="+6"><number>1283603279</number></phone>
        <phone code="+6"><number>1659964668</number></phone>
    </person>
    ...
</persons>

Output

One JSON object per person to STDOUT, preserving order:

{
    "id": 1512376,
    "age": 30,
    "height": 169.1,
    "married": true,
    "phones": [
        {
            "code": "+6",
            "number": 1283603279
        },
        {
            "code": "+6",
            "number": 1659964668
        }
    ]
}

Constraints

  • Preserve the order of persons
  • Omit the phones field if the phone array is empty
  • Maximum number of phones per person is 3
Date AuthorLanguageStatus Score
Apr 20, 2026 19:07Charles CabergsCharles CabergsCPPg++13.3.0Success10,828+12.37 RP
Apr 20, 2026 18:05Charles CabergsCharles CabergsCPPg++13.3.0Success11,204
Apr 20, 2026 16:25BenBenCPPg++14.2.0Success37,932+69.91 RP
Apr 20, 2026 15:22BenBenCPPclang++18.1.3Success51,621+193.72 RP
Apr 20, 2026 15:00BenBenCPPclang++18.1.3Error
Apr 20, 2026 14:13BenBenCPPclang++18.1.3Error
Apr 20, 2026 14:07BenBenCPPg++14.2.0Error
Apr 20, 2026 14:07BenBenCPPg++13.3.0Error
Apr 20, 2026 14:07BenBenCPPclang++18.1.3Error
Apr 20, 2026 13:52olliecrowolliecrowZIG0.14.0Success7,277+2.07 RP
Apr 20, 2026 13:50olliecrowolliecrowRUSTrust-1.94.0Success9,696
Apr 20, 2026 13:44olliecrowolliecrowCPPg++13.3.0Success4,571
Apr 20, 2026 13:36Dominique GarmierDominique GarmierRUSTrust-1.95.0Success5,629
Apr 20, 2026 13:32Dominique GarmierDominique GarmierCPPclang++18.1.3Success8,712
Apr 19, 2026 04:22olliecrowolliecrowCPPclang++18.1.3Success4,274
Apr 19, 2026 04:18olliecrowolliecrowCPPclang++18.1.3Success4,326
Apr 19, 2026 04:15Charles CabergsCharles CabergsCPPg++13.3.0Success10,975+108.46 RP
Apr 18, 2026 21:23Charles CabergsCharles CabergsCPPg++13.3.0Error
Apr 18, 2026 15:03Charles CabergsCharles CabergsCPPg++13.3.0Success12,458+20.41 RP
Apr 18, 2026 14:48olliecrowolliecrowCSHARP9.0.14Success8,656
Apr 18, 2026 11:35Charles CabergsCharles CabergsCPPg++13.3.0Success20,439
Apr 18, 2026 08:01Charles CabergsCharles CabergsCPPg++13.3.0Success12,783+782.29 RP
Apr 18, 2026 05:23Charles CabergsCharles CabergsCPPg++13.3.0Error
Apr 18, 2026 01:25olliecrowolliecrowCSHARP9.0.14Success7,492
Apr 18, 2026 00:28olliecrowolliecrowCSHARP9.0.14Success9,098
Apr 17, 2026 02:59olliecrowolliecrowRUSTrust-1.94.0Success4,476
Apr 17, 2026 02:55olliecrowolliecrowRUSTrust-1.94.0Success4,426
Apr 17, 2026 02:10olliecrowolliecrowRUSTrust-1.94.0Success4,215+17.88 RP
Apr 16, 2026 20:18olliecrowolliecrowCSHARP9.0.14Success5,282
Apr 16, 2026 19:56olliecrowolliecrowRUSTrust-1.94.0Success4,247+101.84 RP
Apr 16, 2026 19:45olliecrowolliecrowRUSTrust-1.94.0Success6,704
Apr 16, 2026 19:37olliecrowolliecrowZIG0.14.0Success38,307
Apr 16, 2026 19:30olliecrowolliecrowCPPclang++18.1.3Success4,469
Apr 16, 2026 08:36olliecrowolliecrowCPPg++13.3.0Success4,378
Apr 16, 2026 03:30olliecrowolliecrowCPPg++13.3.0Success6,619
Apr 16, 2026 02:30olliecrowolliecrowCPPg++13.3.0Success4,346
Apr 16, 2026 02:15olliecrowolliecrowCPPg++13.3.0Success4,186+18.12 RP
Apr 16, 2026 02:12olliecrowolliecrowCPPg++13.3.0Success4,218+58.12 RP
Apr 16, 2026 02:08olliecrowolliecrowCPPg++13.3.0Success4,324+5.87 RP
Apr 15, 2026 01:09olliecrowolliecrowCSHARP9.0.14Success12,462
Apr 9, 2026 16:41olliecrowolliecrowCSHARP9.0.14Success12,171
Apr 9, 2026 15:09olliecrowolliecrowCSHARP9.0.14Success17,801
Apr 9, 2026 11:50olliecrowolliecrowCSHARP9.0.14Success15,897
Apr 9, 2026 04:16olliecrowolliecrowCSHARP9.0.14Success19,429
Apr 8, 2026 12:38olliecrowolliecrowCPPg++13.3.0Error
Apr 8, 2026 12:31olliecrowolliecrowCPPg++13.3.0Success6,764
Apr 8, 2026 12:28olliecrowolliecrowCPPg++13.3.0Success13,253
Apr 8, 2026 12:16olliecrowolliecrowCPPg++13.3.0Success7,232
Apr 8, 2026 12:15olliecrowolliecrowCPPclang++18.1.3Success7,833
Apr 8, 2026 12:05olliecrowolliecrowCPPg++13.3.0Success7,412
Apr 8, 2026 11:59olliecrowolliecrowCPPg++13.3.0Success7,490
Apr 8, 2026 11:54olliecrowolliecrowCPPg++13.3.0Success7,987
Apr 8, 2026 11:52olliecrowolliecrowCPPg++13.3.0Success9,119
Apr 8, 2026 11:39olliecrowolliecrowCPPg++13.3.0Success8,750
Apr 8, 2026 11:26olliecrowolliecrowCPPg++13.3.0Success5,182
Apr 7, 2026 05:43olliecrowolliecrowCPPclang++18.1.3Success5,139
Apr 7, 2026 05:39olliecrowolliecrowCPPg++13.3.0Success5,256
Apr 7, 2026 05:34olliecrowolliecrowCPPg++13.3.0Success11,760
Apr 7, 2026 05:27olliecrowolliecrowCPPclang++18.1.3Success5,182
Apr 7, 2026 05:21olliecrowolliecrowCPPclang++18.1.3Success5,162
Apr 7, 2026 05:20olliecrowolliecrowCPPg++13.3.0Success5,112
Apr 7, 2026 05:15olliecrowolliecrowCPPg++13.3.0Success5,325
Apr 7, 2026 05:09olliecrowolliecrowCPPg++13.3.0Success5,140
Apr 7, 2026 05:03olliecrowolliecrowCPPg++13.3.0Success5,159
Apr 7, 2026 04:42olliecrowolliecrowCPPclang++18.1.3Success5,177
Apr 7, 2026 04:39olliecrowolliecrowCPPg++13.3.0Success7,011
Apr 7, 2026 04:38olliecrowolliecrowCPPg++13.3.0Success5,148
Apr 7, 2026 04:34olliecrowolliecrowCPPg++13.3.0Success7,061
Apr 7, 2026 04:31olliecrowolliecrowCPPclang++18.1.3Success5,191
Apr 6, 2026 21:39olliecrowolliecrowRUSTrust-1.94.0Success9,667
Apr 2, 2026 05:55olliecrowolliecrowRUSTrust-1.94.1Success9,784
Apr 2, 2026 05:10olliecrowolliecrowCSHARP9.0.14Success19,439
Mar 31, 2026 09:30Dominique GarmierDominique GarmierRUSTrust-1.94.1Success5,389+16.04 RP
Mar 30, 2026 19:58Dominique GarmierDominique GarmierCPPclang++18.1.3Success5,827
Mar 30, 2026 19:51Dominique GarmierDominique GarmierCPPclang++18.1.3Success8,641
Mar 30, 2026 18:40Dominique GarmierDominique GarmierGOgo1.26.1Success10,303
Mar 30, 2026 18:34Dominique GarmierDominique GarmierRUSTrust-1.94.1Success5,618
Mar 30, 2026 17:58Dominique GarmierDominique GarmierCPPclang++18.1.3Success8,780
Mar 30, 2026 17:39Dominique GarmierDominique GarmierCPPclang++18.1.3Success8,681
Mar 30, 2026 17:36Dominique GarmierDominique GarmierCPPclang++18.1.3Success5,436+17.43 RP
Mar 30, 2026 17:32Dominique GarmierDominique GarmierCPPclang++18.1.3Success5,488+312.50 RP
Mar 30, 2026 17:23Dominique GarmierDominique GarmierCPPclang++18.1.3Success6,624+110.67 RP
Mar 30, 2026 17:21Dominique GarmierDominique GarmierCPPclang++18.1.3Error
Mar 30, 2026 17:17Dominique GarmierDominique GarmierCPPg++13.3.0Error
Mar 30, 2026 00:04Dominique GarmierDominique GarmierRUSTrust-1.94.1Success7,327
Mar 25, 2026 20:56Dominique GarmierDominique GarmierZIG0.13.0Success155,924
Mar 25, 2026 20:27Dominique GarmierDominique GarmierZIG0.13.0Success17,091
Mar 25, 2026 20:01Dominique GarmierDominique GarmierZIG0.13.0Success16,953
Mar 25, 2026 04:31Dominique GarmierDominique GarmierGOgo1.26.1Success38,258
Mar 23, 2026 00:37Josu San MartinJosu San MartinCPPclang++18.1.3Success5,006
Mar 22, 2026 23:39Josu San MartinJosu San MartinCPPclang++18.1.3Error
Mar 22, 2026 21:34Dominique GarmierDominique GarmierCPPclang++18.1.3Success7,535
Mar 22, 2026 19:13olliecrowolliecrowCSHARP9.0.14Success18,739
Mar 22, 2026 16:03Dominique GarmierDominique GarmierGOgo1.26.1Error
Mar 22, 2026 15:47Dominique GarmierDominique GarmierRUSTrust-1.94.0Success7,334
Mar 22, 2026 08:14Dominique GarmierDominique GarmierCSHARP9.0.14Success78,280
Mar 22, 2026 08:01Dominique GarmierDominique GarmierCSHARP9.0.14Error
Mar 22, 2026 07:55Dominique GarmierDominique GarmierCSHARP9.0.14Error
Mar 22, 2026 07:50Dominique GarmierDominique GarmierCSHARP9.0.14Error
Mar 21, 2026 19:37Josu San MartinJosu San MartinCPPclang++18.1.3Error