{"id":1074,"date":"2026-01-06T15:47:13","date_gmt":"2026-01-06T07:47:13","guid":{"rendered":"https:\/\/www.guanhaobo.cn\/?p=1074"},"modified":"2026-01-06T15:47:13","modified_gmt":"2026-01-06T07:47:13","slug":"leetcode-4-%e5%af%bb%e6%89%be%e4%b8%a4%e4%b8%aa%e6%ad%a3%e5%ba%8f%e6%95%b0%e7%bb%84%e7%9a%84%e4%b8%ad%e4%bd%8d%e6%95%b0","status":"publish","type":"post","link":"https:\/\/www.guanhaobo.cn\/?p=1074","title":{"rendered":"LeetCode 4 \u2013 \u5bfb\u627e\u4e24\u4e2a\u6b63\u5e8f\u6570\u7ec4\u7684\u4e2d\u4f4d\u6570"},"content":{"rendered":"

\u9898\u76ee\u63cf\u8ff0<\/h1>\n

\u7ed9\u5b9a\u4e24\u4e2a\u5927\u5c0f\u5206\u522b\u4e3a m \u548c n \u7684\u6b63\u5e8f\uff08\u4ece\u5c0f\u5230\u5927\uff09\u6570\u7ec4 nums1 \u548c nums2\u3002\u8bf7\u4f60\u627e\u51fa\u5e76\u8fd4\u56de\u8fd9\u4e24\u4e2a\u6b63\u5e8f\u6570\u7ec4\u7684 \u4e2d\u4f4d\u6570 \u3002
\n\u7b97\u6cd5\u7684\u65f6\u95f4\u590d\u6742\u5ea6\u5e94\u8be5\u4e3a O(log (m+n)) \u3002<\/p>\n

\u9898\u76ee\u5206\u6790<\/h1>\n

\u8bbe\u603b\u6570\u91cf\u4e3a sum\uff0c\u95ee\u9898\u53ef\u4ee5\u8f6c\u5316\u4e3a
\n– sum \u662f\u5947\u6570\uff0c\u5bfb\u627e\u7b2c sum \/ 2 + 1<\/code> \u4e2a\u6570\u5b57
\n– sum \u662f\u5076\u6570\uff0c\u5bfb\u627e\u7b2c sum \/ 2<\/code> \u548c sum \/ 2 + 1<\/code> \u4e2a\u6570\u5b57\uff0c\u518d\u53d6\u5e73\u5747\u503c<\/p>\n

\u56e0\u6b64\u95ee\u9898\u8f6c\u5316\u4e3a\u5728 2 \u4e2a\u6709\u5e8f\u6570\u7ec4\u4e2d\u5bfb\u627e\u7b2c k \u5c0f\u7684\u6570\u5b57\u3002
\n\u5206\u522b\u53d6 2 \u4e2a\u6570\u7ec4\u4e2d\u7b2c k \/ 2 \u4e2a\u6570\u5b57 x1 \u548c x2\uff1a
\n– x1 < x2\uff1a x1 \u81f3\u591a\u662f\u7b2c k – 1 \u4e2a\u6570\u5b57\uff0cx1 \u53ca\u5de6\u4fa7\u90fd\u53ef\u4ee5\u4e22\u5f03\u6389\uff0c\u9012\u5f52\u5904\u7406 x1 \u540e\u9762\u7684\u6570\u5b57\u548c nums2
\n– x1 >= x2\uff1a x2 \u81f3\u591a\u662f\u7b2c k – 1 \u4e2a\u6570\u5b57\uff0cx2 \u53ca\u5de6\u4fa7\u90fd\u53ef\u4ee5\u4e22\u5f03\u6389\uff0c\u9012\u5f52\u5904\u7406 x2 \u540e\u9762\u7684\u6570\u5b57\u548c nums1<\/p>\n

\u8fd9\u6837\u6bcf\u6b21\u53ef\u4ee5\u4e22\u5f03 k \/ 2 \u4e2a\u6570\u5b57\uff0c\u9012\u5f52\u51fa\u53e3\u662f num1 \u548c num2 \u4e2d\u6709\u4e00\u4e2a\u4e3a\u7a7a\uff0c\u6216 k = 1\uff08\u4e24\u6570\u7ec4\u7684\u7b2c\u4e00\u4e2a\u6570\u5b57\u53d6\u6700\u5c0f\u503c\uff09\u3002
\nk \u548c sum \u6210\u6b63\u6bd4\uff0c\u56e0\u6b64\u65f6\u95f4\u590d\u6742\u5ea6 O(log(m + n)).<\/p>\n

Java<\/h1>\n
public double findMedianSortedArrays(int[] nums1, int[] nums2) {\n    int sum = nums1.length + nums2.length;\n    if (sum % 2 == 0) {\n        int ans = findK(nums1, 0, nums2, 0, sum \/ 2) + findK(nums1, 0, nums2, 0, sum \/ 2 + 1);\n        return ans \/ 2.0;\n    } else {\n        return findK(nums1, 0, nums2, 0, sum \/ 2 + 1);\n    }\n}\n\nprivate int findK(int[] nums1, int start1, int[] nums2, int start2, int k) {\n    if (start1 == nums1.length) {\n        return nums2[start2 + k - 1];\n    }\n    if (start2 == nums2.length) {\n        return nums1[start1 + k - 1];\n    }\n    if (k == 1) {\n        return Math.min(nums1[start1], nums2[start2]);\n    }\n\n    int mid = k \/ 2 - 1;\n    int index1 = nums1.length > start1 + mid ? start1 + mid : nums1.length - 1;\n    int index2 = nums2.length > start2 + mid ? start2 + mid : nums2.length - 1;\n    if (nums1[index1] < nums2[index2]) {\n        return findK(nums1, index1 + 1, nums2, start2, k - (index1 - start1 + 1));\n    } else {\n        return findK(nums1, start1, nums2, index2 + 1, k - (index2 - start2 + 1));\n    }\n}\n<\/code><\/pre>\n
Kotlin<\/h1>\n
fun findMedianSortedArrays(nums1: IntArray, nums2: IntArray): Double {\n    val sum = nums1.size + nums2.size\n    if (sum % 2 == 0) {\n        val ans = findK(nums1, 0, nums2, 0, sum \/ 2) + findK(nums1, 0, nums2, 0, sum \/ 2 + 1)\n        return ans \/ 2.0\n    } else {\n        return findK(nums1, 0, nums2, 0, sum \/ 2 + 1).toDouble()\n    }\n}\n\nprivate fun findK(nums1: IntArray, start1: Int, nums2: IntArray, start2: Int, k: Int): Int {\n    if (start1 == nums1.size) {\n        return nums2[start2 + k - 1]\n    }\n    if (start2 == nums2.size) {\n        return nums1[start1 + k - 1]\n    }\n    if (k == 1) {\n        return min(nums1[start1], nums2[start2])\n    }\n    val mid = k \/ 2 - 1\n    val index1 = if (nums1.size > mid + start1) mid + start1 else nums1.size - 1\n    val index2 = if (nums2.size > mid + start2) mid + start2 else nums2.size - 1\n    return if (nums1[index1] < nums2[index2]) {\n        findK(nums1, index1 + 1, nums2, start2, k - (index1 - start1 + 1))\n    } else {\n        findK(nums1, start1, nums2, index2 + 1, k - (index2 - start2 + 1))\n    }\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u9898\u76ee\u63cf\u8ff0 \u7ed9\u5b9a\u4e24\u4e2a\u5927\u5c0f\u5206\u522b\u4e3a m \u548c n \u7684\u6b63\u5e8f\uff08\u4ece\u5c0f\u5230\u5927\uff09\u6570\u7ec4 nums1 \u548c nums2\u3002\u8bf7\u4f60\u627e\u51fa\u5e76\u8fd4\u56de\u8fd9 […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[20,32,81],"class_list":["post-1074","post","type-post","status-publish","format-standard","hentry","category-algo","tag-leetcode","tag-32","tag-81"],"_links":{"self":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/1074","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1074"}],"version-history":[{"count":1,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/1074\/revisions"}],"predecessor-version":[{"id":1075,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/1074\/revisions\/1075"}],"wp:attachment":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1074"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1074"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1074"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}