{"id":661,"date":"2025-12-18T15:35:06","date_gmt":"2025-12-18T02:35:06","guid":{"rendered":"https:\/\/thesudoku.com\/blog\/?page_id=661"},"modified":"2025-12-22T11:00:08","modified_gmt":"2025-12-21T22:00:08","slug":"x-loop","status":"publish","type":"page","link":"https:\/\/thesudoku.com\/blog\/x-loop\/","title":{"rendered":"X-Loop"},"content":{"rendered":"\n<div class=\"wp-block-group content-wrapper has-base-background-color has-background has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\" style=\"min-height:90vh;margin-top:var(--wp--preset--spacing--40);margin-bottom:var(--wp--preset--spacing--40);padding-top:0;padding-bottom:0\">\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-container-core-group-is-layout-b5150c35 wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--40);padding-right:var(--wp--preset--spacing--40);padding-bottom:0;padding-left:var(--wp--preset--spacing--40)\">\n<p class=\"is-style-default\" style=\"font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);font-style:normal;font-weight:700\"><a href=\"https:\/\/thesudoku.com\/blog\/sudoku-rules-normal\/\" data-type=\"page\" data-id=\"73\">&lt; <\/a><a href=\"https:\/\/thesudoku.com\/sudoku-rules-master\/\" data-type=\"page\" data-id=\"644\">Back<\/a><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-container-core-group-is-layout-8dd13e6d wp-block-group-is-layout-constrained\" style=\"padding-right:var(--wp--preset--spacing--60);padding-left:var(--wp--preset--spacing--60)\">\n<p class=\"is-style-text-display is-style-text-display--1\" style=\"font-size:clamp(17.905px, 1.119rem + ((1vw - 3.2px) * 0.99), 28px);font-style:normal;font-weight:800\">X-Loop (X-Cycle)<\/p>\n\n\n\n<p style=\"font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);\">In this strategy, we build loops by alternately chaining weak links and strong links<\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full is-resized is-style-default\" style=\"margin-top:var(--wp--preset--spacing--30);margin-right:0;margin-bottom:0;margin-left:0\"><img loading=\"lazy\" decoding=\"async\" width=\"694\" height=\"694\" src=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7800.png\" alt=\"Weak and strong Sudoku links\" class=\"wp-image-662\" style=\"object-fit:cover;width:349px;height:auto\" srcset=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7800.png 694w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7800-300x300.png 300w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7800-150x150.png 150w\" sizes=\"auto, (max-width: 694px) 100vw, 694px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--20);padding-bottom:var(--wp--preset--spacing--20)\">\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" style=\"margin-top:var(--wp--preset--spacing--20);margin-bottom:var(--wp--preset--spacing--20)\"\/>\n\n\n\n<ol class=\"wp-block-list\">\n<li style=\"border-style:none;border-width:0px;font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);\">A strong link means that if a candidate is OFF in the first cell, it must be ON in the second cell, and vice versa. Weak links are less certain: if a candidate is ON in one cell, the other must be OFF, but if it is OFF in the first cell, the second cell could still be ON or OFF (if there are more than two candidates in the unit)<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full is-resized is-style-default\" style=\"margin-top:var(--wp--preset--spacing--30);margin-right:0;margin-bottom:0;margin-left:0\"><img loading=\"lazy\" decoding=\"async\" width=\"694\" height=\"694\" src=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7801.png\" alt=\"Weak and strong links explained\" class=\"wp-image-663\" style=\"object-fit:cover;width:349px;height:auto\" srcset=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7801.png 694w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7801-300x300.png 300w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7801-150x150.png 150w\" sizes=\"auto, (max-width: 694px) 100vw, 694px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--20);padding-bottom:var(--wp--preset--spacing--20)\">\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" style=\"margin-top:var(--wp--preset--spacing--20);margin-bottom:var(--wp--preset--spacing--20)\"\/>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li style=\"border-style:none;border-width:0px;font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);\">Consider these cells. This chain forms a continuous loop of candidate 5<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full is-resized is-style-default\" style=\"margin-top:var(--wp--preset--spacing--30);margin-right:0;margin-bottom:0;margin-left:0\"><img loading=\"lazy\" decoding=\"async\" width=\"697\" height=\"697\" src=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7836.png\" alt=\"X-Loop chain example\" class=\"wp-image-664\" style=\"object-fit:cover;width:349px;height:auto\" srcset=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7836.png 697w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7836-300x300.png 300w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7836-150x150.png 150w\" sizes=\"auto, (max-width: 697px) 100vw, 697px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\" style=\"padding-top:var(--wp--preset--spacing--20);padding-bottom:var(--wp--preset--spacing--20)\">\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" style=\"margin-top:var(--wp--preset--spacing--20);margin-bottom:var(--wp--preset--spacing--20)\"\/>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li style=\"border-style:none;border-width:0px;font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);\">At each end of any link, there must be a candidate 5 in one of the two cells. This allows us to safely eliminate 5 from any cell that can see both of these cells at the same time<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full is-resized is-style-default\" style=\"margin-top:var(--wp--preset--spacing--30);margin-right:0;margin-bottom:var(--wp--preset--spacing--30);margin-left:0\"><img loading=\"lazy\" decoding=\"async\" width=\"697\" height=\"697\" src=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7837.png\" alt=\"X-Loop technique, elimination of the candidate\" class=\"wp-image-665\" style=\"object-fit:cover;width:349px;height:auto\" srcset=\"https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7837.png 697w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7837-300x300.png 300w, https:\/\/thesudoku.com\/blog\/wp-content\/uploads\/2025\/12\/Group-7837-150x150.png 150w\" sizes=\"auto, (max-width: 697px) 100vw, 697px\" \/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" style=\"margin-top:var(--wp--preset--spacing--20);margin-bottom:var(--wp--preset--spacing--20)\"\/>\n\n\n\n<div class=\"wp-block-group alignwide is-content-justification-space-between is-nowrap is-layout-flex wp-container-core-group-is-layout-7f2ee5f7 wp-block-group-is-layout-flex\" style=\"padding-top:0;padding-right:var(--wp--preset--spacing--60);padding-bottom:var(--wp--preset--spacing--60);padding-left:var(--wp--preset--spacing--60)\">\n<p style=\"font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);font-style:normal;font-weight:600\"><a href=\"https:\/\/thesudoku.com\/blog\/hidden-pairs\/\" data-type=\"page\" data-id=\"447\">&lt; <\/a><a href=\"https:\/\/thesudoku.com\/skyscraper\/\" data-type=\"page\" data-id=\"613\">Skyscraper<\/a><\/p>\n\n\n\n<p style=\"font-size:clamp(14px, 0.875rem + ((1vw - 3.2px) * 0.392), 18px);font-style:normal;font-weight:600\"><a href=\"https:\/\/thesudoku.com\/2-string-kite\/\" data-type=\"page\" data-id=\"669\">2-String Kite><\/a><\/p>\n<\/div>\n<\/div>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&lt; Back X-Loop (X-Cycle) In this strategy, we build loops by alternately chaining weak links and strong links &lt; Skyscraper 2-String Kite><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-no-title","meta":{"footnotes":""},"categories":[116],"tags":[],"class_list":["post-661","page","type-page","status-publish","hentry","category-master-techniques"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.7 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>X-Loop - TheSudoku.com<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/thesudoku.com\/blog\/x-loop\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"X-Loop - TheSudoku.com\" \/>\n<meta property=\"og:description\" content=\"&lt; 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