It looks like this is a web page, not a feed. I looked for a feed associated with this page, but couldn't find one. Please enter the address of your feed to validate.

Source: https://leetcode.com/u/pqxwbcfahd/

  1. <!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="360"></head><body><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "leetcode.com",cType: 'managed',cRay: '93abfaaa9cded688',cH: 'En0yrwn4tEs12LGBK6tw3Ulco.4XJN7aNW78BUn60g8-1746403452-1.2.1.1-qFK1qUSP4MkkOlzoZ3BafJhRRGthLzqIXlJgJZZ.Vd7GNQSOd.5V.8UwJoA997si',cUPMDTk: "\/u\/pqxwbcfahd\/?__cf_chl_tk=fyZPlRJ6V3jvPfKZc2yxVfp4fdOuVAl_Jyw.739QWFY-1746403452-1.0.1.1-ECNlFZnDNeHuPoY25i5ZUJQQ84Yy_iatOEuKa5aoI4s",cFPWv: 'g',cITimeS: '1746403452',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/u\/pqxwbcfahd\/?__cf_chl_f_tk=fyZPlRJ6V3jvPfKZc2yxVfp4fdOuVAl_Jyw.739QWFY-1746403452-1.0.1.1-ECNlFZnDNeHuPoY25i5ZUJQQ84Yy_iatOEuKa5aoI4s",md: "BI2TzHf7E_NGFlGrdUm9RhwgSGw8eaz5mtbnzxe5d9s-1746403452-1.2.1.1-B4vdaY2vmPnpGp_FVVIKQGUhwWrhUxMqEpGpPAquhVNCwKlfgyCq7J5GI6TLhN0ykTU0FvqjY4oUNsuYmYij8.8Q_eySrTC8yz50izGlZ9Z3oT0qMNyFAk9X7emrSSiFAfck45nfBM3oqrQo6MJ7TSndlO4DCPsocZHIwoHm6_4o73gIiO1jB5BA60kED2jdtKYLUnIQ7xEt3zmfFT0I2WjmzOB_yikQ.t0HNkGq_7uMQTQjOXBxAWlJIzt3fbfotiMHz1LlsxL4G81yy6lJM48i0aBw895bfA4lEa8T7mxva.GxzJUZPOvwCbXj3kQnGr_zW_8hm.VWB5Pivv.1wnQE4DdvBSc_jjX9GQo3jbsIQuGCGyo_vBsVTQIzOqL9DCqKhsR.dMmWzJ0BEqqAxpGHk8_zSm3Cx6xb80oECwoi6tvNgnNxuRxYrfZfu6bGliaWZQgkUpUkUmPn9ZYBAQ9hmp8tSda9cS.EL2XyJqraEzjLeUu8_gH_hAvkvVXXXs8m7Yt34rtSw1YbNiwtWS3IY7GgHbN.s6Yr__xbN4FgjArPCw40N_XcDFOrKMJWvN0f6nycr7sJ8yGu_1es2sWbiOsJbNOvRCR.iu2_lz77iq9kVMjM3kebsJdSbq.skvUYuPwerDSnKilTgSmcxwID8SBn9NdWkGMFjNuEYm3WbeoyCNO5oZZbu_OqzTAzKQOMW.cqc55Q6HffzVZVAh7o_N1n9rCBM12E6lllTA_bRmUoaX7nKXjCmejLWehBUJVxNWPnYEYbN0EJ74S4nsnfIZgmMjiOtqviJhOznsNx7XVEkmFXvxl3EVZYAUoonl2NillW7Dy6AId6u05Vk8.68cMiMg1YlA8aHBx18CuA8zUD2RZOpgWcI_lQAo0Uhk5gaHgUPC2TInWsqbyo4iQPLqEO8HKmZZMxcwScMb0aNGKihFGHOosvDbPJBdy8c3kT0QTeuDLv93CeFyIdfMoexH7uDwx_ZG7otwaFmTYlETiEjJWQkE0CYUcEXOvr",mdrd: "9E7k.0gsAe4DEcbmnGqWwDSOyLd5x93wFuIQ9Z.ix4Q-1746403452-1.2.1.1-h4jDtKijY_pgaP3GizSURDCODEyt92t8z3tHWl8Bmpzg5kNKNj9ZpgAvx7pp5KggeLWUB7yNBdMePpdMM1QAamaLSMo51vxG1e4fOi5LNl_KwgVXB5PJSvzFQrsI3pBmBx.Qt9vSk5npwuW3jFm0R2wMDSOZZTlQu_SwNF_IDaY0A9JHer5v_3iKjpgrqa8IU_xeaoGfgRTUGW0bmDz_WM3D1ZM6NEWUzj3p2f0woCr_CwKghyfw1QMFWAB4f3od2ANvbIMGgaPY6etJDQ8Osa61rL5xxVFs.s6KRzpo.g7_IPTnrUWarg.q2sxAHyDlhMW00en1XsgWdA7I1kOx2qOUVoHhhSYtgatvUQCMFbba_KCrf72h8o5Y0jpOh32.BobjOFQtbNJ0388W9rW57tF4o7DW_IUk_8kU_GnHd6ZbI37NUpnuwASyqGMSVFOLpvmFzAHlfxsYMp8A9ph7KyDCIPMHWmKXIRvvKZypyfSjYjaY4gBoK1Tv._9BLpC4hFybZmtrHsKaTTpEFcKiMdJrGOdLRQRy6CwYNULfHrJfvJxItAfDAxQP2T1V4Q3N16IqO3o_Y3YE4p7Ad6ZFIWPAyxdQOt.Ge3rCuji9Xrx3c20XvDjMSKjLpqcEatQ_CX8NzFoL2cX1u7M3WeWgjMYfct43L8v8TXLIwduYF.hPluKqJ32jfXEAANiTvFIyAn6MzHw0rXohWmJtJRcT1SuWnGtE9iuhdKk.d4KfVYFifp_Uv6VKo13mAzIwOgdZtjjrRKsiwiL6boBDM3.R2B7k7rA_uIPEMss3pDGi0MDmg1axGMZDVdsigVAXmlSNc4bhie6t5bOA.rY9DefsIBgTVEeJ38XdKKZ8jdP12VSj8umkql85f2PeOjYELyyidy7EoGNwyauggIeKWHv6ToOZGCZOGSwRNa7BrLMqXAdJSHj.mvAUAEYK0CpY6iz4EH9.BibOsnigj9xakG1bSx.wsf43Fceuf9X6MWlC2F3_Scrvbqzt9h1CmQ8fx3KqAoLA2mmz6heKW5OT0RMza67o7E1Yw1MGyKnWKLP4t0I4ZMY.Iq6Cg18yVLyTJT8wj7KXEsZ4Un7X.d7yOZ7yc6WKy9wzflvXnvmtle2S0hMeEJmwKli4ZTG3A46fIM1XzlzsKDt8yngwjgZRwY74ITDrBljPWDheC5dcx98ORmsXwlxpzZnMpqsNu1DVWvQGwANpIST9QQZ8YwNYA3IXXSiwruOFObSvWUWlAl1UwaCzQlk75CtO2pKP_kV3nmySFF1332NFTLQpa.5QR9ChsByrFnnA1hWhu10HkhgXNtarbP83MaJUrh5hIOr.DqiuMFLUNfGEAUayolYsYPiwaa.c4QhJGcT7YRzDUF.I3BwueC9Pd.992zWT39VaFmFRDGN_IGG.lb_ot8ujfluCzYnIytIfOw_KWdPiAn2_QxZn9Lz9uSSMFl5Tg9tP4i3YWqPIR3p0VgR9sUpCv7cEvo5mMwMWFYawEfmAhCXMk8WrNAK2MXYG4nsE4I1wpR9pwDZOEoFhCYBP5dC80eUuKN16_g3fstKU_FzyORvdVDiFMLUhHwMZQnsOYxHeioXAWjRYdUJZzEmY8__MVNsO7pDj_b7yhOdxN92H5sxci7kIHBksUJvBMGbpWSE0nK04eLGrnVFLPddyWuqMcMVgPgJXSHHXpWYrGro7ZOeNE1kPm3dw7XANw3_wzO5s4XwesoOgKkiA0ciFSAAMB7j2nCGryOdQLrBkoWPvqEo48PPsKmVm8xxVwhgfDjVIC4d1Yg7IuJN.LwVX18WhcFlVplb9hkJdYXKsxIh0a0Z0exvReqjOBZlx6DEzol5k8GaQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=93abfaaa9cded688';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/u\/pqxwbcfahd\/?__cf_chl_rt_tk=fyZPlRJ6V3jvPfKZc2yxVfp4fdOuVAl_Jyw.739QWFY-1746403452-1.0.1.1-ECNlFZnDNeHuPoY25i5ZUJQQ84Yy_iatOEuKa5aoI4s" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>
Copyright © 2002-9 Sam Ruby, Mark Pilgrim, Joseph Walton, and Phil Ringnalda