{"id":425800,"date":"2021-03-31T00:59:27","date_gmt":"2021-03-30T16:59:27","guid":{"rendered":"http:\/\/4563.org\/?p=425800"},"modified":"2021-03-31T00:59:27","modified_gmt":"2021-03-30T16:59:27","slug":"%e9%ab%98%e9%a2%91%e9%a2%98%e9%9d%a2%e8%af%95%e7%bb%8f%e5%85%b8%e9%a2%98%e7%9b%ae-%e5%89%8d%e7%bc%80%e5%92%8c%e6%95%b0%e7%bb%84","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=425800","title":{"rendered":"[\u9ad8\u9891\u9898]\u9762\u8bd5\u7ecf\u5178\u9898\u76ee–\u524d\u7f00\u548c\u6570\u7ec4"},"content":{"rendered":"
\n
\n
\n

[\u9ad8\u9891\u9898]\u9762\u8bd5\u7ecf\u5178\u9898\u76ee–\u524d\u7f00\u548c\u6570\u7ec4 <\/h1>\n

<\/p>\n

\n
\u8cc7\u6df1\u5927\u4f6c : youthes <\/span> <\/i> 6<\/span> <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
\u4e0d\u5f97\u4e0d\u8bf4\uff0c\u5237\u9898\u5df2\u7ecf\u548c\u722c\u5c71\u3001\u6e9c\u5a03\u4e00\u6837\uff0c\u6210\u4e3a\u6e7e\u533a\u4e09\u4fd7\uff0c\u57fa\u672c\u51e0\u4e2a\u6e7e\u533a\u7684\u5de5\u7a0b\u5e08\u78b0\u5728\u4e00\u8d77\uff0c\u8ba8\u8bba\u7684\u8bdd\u9898\u603b\u8df3\u4e0d\u51fa\u8fd9\u4e2a\u5708\u3002\u722c\u5c71\uff0c\u54e6\u4e0d\uff0c\u5237\u9898\u4f5c\u4e3a\u4e00\u4e2a\u8d2f\u7a7f\u7801\u519c\u6574\u4e2a\u804c\u4e1a\u751f\u6daf\u7684\u5fc5\u987b\u54c1\uff08\u5c31\u7b97\u662f\u6211\u76ee\u524d\u5446\u7684\u5fae\u8f6f\u8c37\u6b4c\u8fd9\u79cd\u517b\u8001\u516c\u53f8\u4e5f\u603b\u5f97\u8df3\u4e00\u8df3\uff0c\u6bd5\u7adf\u96ea\u82b1\u7684\u5927\u5305\u88f9\u662f\u771f\u9999\u554a\uff09\uff0c\u51e0\u5e74\u6765\u57fa\u672c\u6bcf\u5929\u4e0d\u95f4\u65ad\u7684\u5237\uff0c\u7b97\u662f\u5bf9\u8fd9\u4e00\u5757\u7565\u6709\u5fc3\u5f97\u3002\u5e16\u5b50\u7684\u524d\u534a\u90e8\u5206\u60f3\u5206\u4eab\u4e00\u4e9b\u6211\u4f5c\u4e3a\u9762\u8bd5\u5b98\u7684\u5e38\u51fa\u7684\u4e00\u4e9b\u7ecf\u5178\u9898\u76ee\uff0c\u4ee5\u53ca\u9898\u76ee\u601d\u8def\u7684\u89e3\u6790\u4ee5\u53ca\u4e00\u4e9b\u540c\u7c7b\u9898\u7684\u5f52\u7eb3\uff0c\u5e16\u5b50\u7684\u540e\u534a\u90e8\u5206\u6211\u4f1a\u53c2\u8003\u575b\u53cb\u4eec\u7684\u7559\u8a00\u548c\u62cd\u7816\uff0c\u6765\u51b3\u5b9a\u540e\u9762\u7684\u8d70\u5411<\/p>\n

\u5e16\u5b50\u4f1a\u957f\u671f\u4fdd\u6301\u66f4\u65b0\uff0c\u53ea\u8981\u662f\u5e26\u5a03\u7684\u95f4\u9699\u5c31\u4f1a\u5077\u5077\u4e0a\u6765\u66f4\u4e00\u4e0b\uff0c\u5c3d\u91cf\u4fdd\u6301\u6bcf\u5468\u4e24\u66f4\u3002<\/p>\n

\u672c\u671f\u6211\u4eec\u5206\u4eab \u9762\u8bd5\u7ecf\u5178\u9898\u76ee–\u524d\u7f00\u548c\u6570\u7ec4<\/p>\n

\u7531\u4e8e\u592a\u591a\u4eba\u52a0\u6211 VX\uff0c\u6211\u4e5f\u521b\u5efa\u4e86\u4e00\u4e2a\u7b97\u6cd5\u5de5\u4f5c\u4ea4\u6d41\u7fa4\uff0c\u5927\u5bb6\u611f\u5174\u8da3\u53ef\u4ee5\u52a0\u6211\u62c9\u4f60\u8fdb\u7fa4<\/p>\n

\u6211\u7684 VX\uff1asxxzs3998 \u4e0d\u7ba1\u662f\u5177\u4f53\u7684\u9898\u76ee\u8ba8\u8bba\u8fd8\u662f\u7ed9\u5e16\u5b50\u7684\u5efa\u8bae\u548c\u62cd\u7816\uff0c\u6216\u8005\u60f3\u8fdb\u7fa4\u90fd\u6b22\u8fce\u6dfb\u52a0\uff08\u8bb0\u5f97\u52a0\u6211\u8981\u5907\u6ce8 v2 \uff09 <\/p><\/div>\n

\u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (3<\/span>) <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n
    \n
  • \n
    \n
    \n
    \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : youthes <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u4eca\u5929\u6765\u804a\u4e00\u9053\u7b80\u5355\u5374\u5341\u5206\u5de7\u5999\u7684\u7b97\u6cd5\u95ee\u9898\uff1a\u7b97\u51fa\u4e00\u5171\u6709\u51e0\u4e2a\u548c\u4e3a k \u7684\u5b50\u6570\u7ec4\u3002<\/p>\n

    \u7ed9\u5b9a\u4e00\u4e2a\u6574\u6570\u6570\u7ec4\u548c\u4e00\u4e2a\u6574\u6570\u00a0k\uff0c\u4f60\u9700\u8981\u627e\u5230\u8be5\u6570\u7ec4\u4e2d\u548c\u4e3a\u00a0k\u00a0\u7684\u8fde\u7eed\u7684\u5b50\u6570\u7ec4\u7684\u4e2a\u6570\u3002<\/p>\n

    \u793a\u4f8b 1 :<\/p>\n

    \u8f93\u5165:nums = [1,1,1], k = 2
    \u8f93\u51fa: 2 , [1,1] \u4e0e [1,1] \u4e3a\u4e24\u79cd\u4e0d\u540c\u7684\u60c5\u51b5\u3002<\/p>\n

    \u90a3\u6211\u628a\u6240\u6709\u5b50\u6570\u7ec4\u90fd\u7a77\u4e3e\u51fa\u6765\uff0c\u7b97\u5b83\u4eec\u7684\u548c\uff0c\u770b\u770b\u8c01\u7684\u548c\u7b49\u4e8e k \u4e0d\u5c31\u884c\u4e86\u3002
    \u5173\u952e\u662f\uff0c\u5982\u4f55\u5feb\u901f\u5f97\u5230\u67d0\u4e2a\u5b50\u6570\u7ec4\u7684\u548c\u5462\uff0c\u6bd4\u5982\u8bf4\u7ed9\u4f60\u4e00\u4e2a\u6570\u7ec4 nums\uff0c\u8ba9\u4f60\u5b9e\u73b0\u4e00\u4e2a\u63a5\u53e3 sum(i, j)\uff0c\u8fd9\u4e2a\u63a5\u53e3\u8981\u8fd4\u56de nums[i..j] \u7684\u548c\uff0c\u800c\u4e14\u4f1a\u88ab\u591a\u6b21\u8c03\u7528\uff0c\u4f60\u600e\u4e48\u5b9e\u73b0\u8fd9\u4e2a\u63a5\u53e3\u5462\uff1f
    \u56e0\u4e3a\u63a5\u53e3\u8981\u88ab\u591a\u6b21\u8c03\u7528\uff0c\u663e\u7136\u4e0d\u80fd\u6bcf\u6b21\u90fd\u53bb\u904d\u5386 nums[i..j]\uff0c\u6709\u6ca1\u6709\u4e00\u79cd\u5feb\u901f\u7684\u65b9\u6cd5\u5728 O(1) \u65f6\u95f4\u5185\u7b97\u51fa nums[i..j] \u5462\uff1f\u8fd9\u5c31\u9700\u8981\u524d\u7f00\u548c\u6280\u5de7\u4e86\u3002 <\/div>\n<\/p><\/div>\n<\/li>\n

  • \n
    \n
    \n
    \u8cc7\u6df1\u5927\u4f6c : Rocketer <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u4e3b\u65b0\u6765\u7684\u5427\uff1f V2 \u600e\u4e48\u66f4\u65b0\u5e16\u5b50\uff1f <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
    \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : youthes <\/span> <\/div>\n
    <\/i> <\/span> <\/div>\n<\/p><\/div>\n
    \u4e00\u3001\u4ec0\u4e48\u662f\u524d\u7f00\u548c<\/p>\n

    \u524d\u7f00\u548c\u7684\u601d\u8def\u662f\u8fd9\u6837\u7684\uff0c\u5bf9\u4e8e\u4e00\u4e2a\u7ed9\u5b9a\u7684\u6570\u7ec4 `nums`\uff0c\u6211\u4eec\u989d\u5916\u5f00\u8f9f\u4e00\u4e2a\u524d\u7f00\u548c\u6570\u7ec4\u8fdb\u884c\u9884\u5904\u7406\uff1a<\/p>\n

    int n = nums.length;
    \/\/ \u524d\u7f00\u548c\u6570\u7ec4
    int[] preSum = new int[n + 1];
    preSum[0] = 0;
    for (int i = 0; i < n; i++)
    preSum[i + 1] = preSum[i] + nums[i];<\/p>\n

    \u8fd9\u4e2a\u524d\u7f00\u548c\u6570\u7ec4 `preSum` \u7684\u542b\u4e49\u4e5f\u5f88\u597d\u7406\u89e3\uff0c`preSum[i]` \u5c31\u662f `nums[0..i-1]` \u7684\u548c\u3002\u90a3\u4e48\u5982\u679c\u6211\u4eec\u60f3\u6c42 `nums[i..j]` \u7684\u548c\uff0c\u53ea\u9700\u8981\u4e00\u6b65\u64cd\u4f5c `preSum[j+1]-preSum[i]` \u5373\u53ef\uff0c\u800c\u4e0d\u9700\u8981\u91cd\u65b0\u53bb\u904d\u5386\u6570\u7ec4\u4e86\u3002<\/p>\n

    \u56de\u5230\u8fd9\u4e2a\u5b50\u6570\u7ec4\u95ee\u9898\uff0c\u6211\u4eec\u60f3\u6c42\u6709\u591a\u5c11\u4e2a\u5b50\u6570\u7ec4\u7684\u548c\u4e3a k\uff0c\u501f\u52a9\u524d\u7f00\u548c\u6280\u5de7\u5f88\u5bb9\u6613\u5199\u51fa\u4e00\u4e2a\u89e3\u6cd5\uff1a<\/p>\n

    int subarraySum(int[] nums, int k) {
    int n = nums.length;
    \/\/ \u6784\u9020\u524d\u7f00\u548c
    int[] sum = new int[n + 1];
    sum[0] = 0;
    for (int i = 0; i < n; i++)
    sum[i + 1] = sum[i] + nums[i];<\/p>\n

    int ans = 0;
    \/\/ \u7a77\u4e3e\u6240\u6709\u5b50\u6570\u7ec4
    for (int i = 1; i <= n; i++)
    for (int j = 0; j < i; j++)
    \/\/ sum of nums[j..i-1]
    if (sum[i] – sum[j] == k)
    ans++;<\/p>\n

    return ans;
    }<\/p>\n

    \u8fd9\u4e2a\u89e3\u6cd5\u7684\u65f6\u95f4\u590d\u6742\u5ea6 `O(N^2)` \u7a7a\u95f4\u590d\u6742\u5ea6 `O(N)`\uff0c\u5e76\u4e0d\u662f\u6700\u4f18\u7684\u89e3\u6cd5\u3002\u4e0d\u8fc7\u901a\u8fc7\u8fd9\u4e2a\u89e3\u6cd5\u7406\u89e3\u4e86\u524d\u7f00\u548c\u6570\u7ec4\u7684\u5de5\u4f5c\u539f\u7406\u4e4b\u540e\uff0c\u53ef\u4ee5\u4f7f\u7528\u4e00\u4e9b\u5de7\u5999\u7684\u529e\u6cd5\u628a\u65f6\u95f4\u590d\u6742\u5ea6\u8fdb\u4e00\u6b65\u964d\u4f4e\u3002 <\/p><\/div>\n<\/p><\/div>\n<\/li>\n

  • \n","protected":false},"excerpt":{"rendered":"

    [\u9ad8\u9891\u9898]\u9762\u8bd5\u7ecf\u5178\u9898\u76ee&#8211…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/425800"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=425800"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/425800\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=425800"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=425800"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=425800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}