{"id":2697,"date":"2022-04-10T21:08:57","date_gmt":"2022-04-10T13:08:57","guid":{"rendered":"https:\/\/www.zeroheart.xyz\/wordpress\/?p=2697"},"modified":"2022-04-11T21:51:28","modified_gmt":"2022-04-11T13:51:28","slug":"%e7%ae%97%e6%b3%95%e5%9f%ba%e7%a1%80%e7%ac%ac%e4%b8%80%e5%a4%a9","status":"publish","type":"post","link":"https:\/\/www.zeroheart.xyz\/wordpress\/?p=2697","title":{"rendered":"\u7b97\u6cd5\u57fa\u7840\u7b2c\u4e00\u5929"},"content":{"rendered":"\n

34. \u5728\u6392\u5e8f\u6570\u7ec4\u4e2d\u67e5\u627e\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u548c\u6700\u540e\u4e00\u4e2a\u4f4d\u7f6e<\/a><\/p>\n\n\n\n

\u8fd9\u9898\u56de\u987e\u4e00\u4e0b\u4e8c\u5206\u6cd5\uff0c\u8981\u627e\u6700\u5de6\u548c\u6700\u53f3\u7684\u8fb9\u754c\uff0c\u5728mid = target\u4e4b\u540e\uff0c\u7ee7\u7eed\u79fb\u52a8mid\u7684\u4f4d\u7f6e\u5373\u53ef\u3002<\/p>\n\n\n\n

\n\/**\n<\/em> 34. \u5728\u6392\u5e8f\u6570\u7ec4\u4e2d\u67e5\u627e\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u548c\u6700\u540e\u4e00\u4e2a\u4f4d\u7f6e\n<\/em> \u7ed9\u5b9a\u4e00\u4e2a\u6309\u7167\u5347\u5e8f\u6392\u5217\u7684\u6574\u6570\u6570\u7ec4 nums\uff0c\u548c\u4e00\u4e2a\u76ee\u6807\u503c target\u3002\u627e\u51fa\u7ed9\u5b9a\u76ee\u6807\u503c\u5728\u6570\u7ec4\u4e2d\u7684\u5f00\u59cb\u4f4d\u7f6e\u548c\u7ed3\u675f\u4f4d\u7f6e\u3002\n<\/em>\n<\/em> \u5982\u679c\u6570\u7ec4\u4e2d\u4e0d\u5b58\u5728\u76ee\u6807\u503c target\uff0c\u8fd4\u56de [-1, -1]\u3002\n<\/em>\n<\/em> \u8fdb\u9636\uff1a\n<\/em>\n<\/em> \u4f60\u53ef\u4ee5\u8bbe\u8ba1\u5e76\u5b9e\u73b0\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(log n) \u7684\u7b97\u6cd5\u89e3\u51b3\u6b64\u95ee\u9898\u5417\uff1f\n<\/em>\n<\/em>\n<\/em> \u793a\u4f8b 1\uff1a\n<\/em>\n<\/em> \u8f93\u5165\uff1anums = [5,7,7,8,8,10], target = 8\n<\/em> \u8f93\u51fa\uff1a[3,4]\n<\/em> \u793a\u4f8b 2\uff1a\n <\/em>\n<\/em> \u8f93\u5165\uff1anums = [5,7,7,8,8,10], target = 6\n<\/em> \u8f93\u51fa\uff1a[-1,-1]\n<\/em> \u793a\u4f8b 3\uff1a\n<\/em>\n<\/em> \u8f93\u5165\uff1anums = [], target = 0\n<\/em> \u8f93\u51fa\uff1a[-1,-1]\n<\/em>\n<\/em>\n<\/em> \u63d0\u793a\uff1a\n<\/em>\n<\/em> 0 <= nums.length <= 10^5\n<\/em> -10^9 <= nums[i] <= 10^9\n<\/em> nums \u662f\u4e00\u4e2a\u975e\u9012\u51cf\u6570\u7ec4\n<\/em> -10^9 <= target <= 10^9\n<\/em>\n<\/em> * <\/em>@author <\/em><\/strong>zeroheart\n<\/em> *\n<\/em> *\/\n<\/em>public class Question34 {\n\n    public int[] searchRange(int[] nums, int target) {\n        int[] res = new int[]{-1,-1};\n        res[0] = binarySearch(nums, target, 1);\n        res[1] = binarySearch(nums, target, 0);\n        return res;\n    }\n\n    public int binarySearch(int[] nums, int target, int left){\n        int res = -1;\n        int low = 0; int high = nums.length - 1;\n        int mid = 0;\n\n        while (low <= high){\n            mid = low + (high-low) \/ 2;\n            if(nums[mid]<target){\n                low = mid + 1;\n            }else if(nums[mid]>target){\n                high = mid - 1;\n            }else {\n                \/\/ \u867d\u7136\u5df2\u7ecf\u627e\u5230\u4e86\uff0c\u4e0d\u8fc7\u4e0d\u4e00\u5b9a\u662f\u6700\u5de6\u8fb9\u7684\u6216\u8005\u6700\u53f3\u8fb9\u7684\n                res = mid;\n                if(left == 1){\n                    \/\/ \u5982\u679c\u8981\u627e\u7684\u662f\u6700\u5de6\u7684\uff0c\u53f3\u8fb9\u7684\u6307\u9488\u7ee7\u7eed\u51cf\u5c0f\u3002\n                    high = mid - 1;\n                }else {\n                    low = mid + 1;\n                }\n            }\n        }\n\n        return res;\n    }\n\n    public int[] searchRange1(int[] nums, int target) {\n        \/\/ \u901a\u8fc7\u4e86\uff0c\u4f46\u662f\u6ca1\u7528\u5230\u7b97\u6cd5\n        int[] res = new int[]{-1,-1};\n\n        for(int i = 0; i<nums.length; i++){\n            if(nums[i] == target && res[0] == -1){\n                res[0] = i;\n            }\n\n            if(nums[i] == target && res[0] != -1 && i == nums.length - 1){\n                res[1] = i;\n                break;\n            }\n\n            if(nums[i] > target && res[0] != -1){\n                res[1] = i-1;\n                break;\n            }\n        }\n\n        if(res[0] == -1){\n            res[1] = -1;\n        }\n\n        if(res[1] < res[0]){\n            res[1] = res[0];\n        }\n\n        return res;\n    }\n\n}<\/pre>\n\n\n\n
33. \u641c\u7d22\u65cb\u8f6c\u6392\u5e8f\u6570\u7ec4<\/a><\/p>\n\n\n\n
\u65cb\u8f6c\u6392\u5e8f\u6570\u7ec4\uff0cnums[0]\u662f\u4e00\u4e2a\u5206\u754c\u70b9\u3002\u8fd9\u9898\u4e5f\u662f\u5229\u7528\u4e8c\u5206\u6cd5\uff0c\u786e\u5b9a\u662f\u5728\u9ad8\u7684\u4e00\u4fa7\u8fd8\u662f\u4f4e\u7684\u4e00\u5c42\u4e4b\u540e\uff0c\u5728\u6bd4\u8f83target\u7684\u5927\u5c0f\u6765\u79fb\u52a8\u6307\u9488\u3002<\/p>\n\n\n\n

\/**
<\/em> 33. \u641c\u7d22\u65cb\u8f6c\u6392\u5e8f\u6570\u7ec4
<\/em> \u6574\u6570\u6570\u7ec4 nums \u6309\u5347\u5e8f\u6392\u5217\uff0c\u6570\u7ec4\u4e2d\u7684\u503c \u4e92\u4e0d\u76f8\u540c \u3002
<\/em>
<\/em> \u5728\u4f20\u9012\u7ed9\u51fd\u6570\u4e4b\u524d\uff0cnums \u5728\u9884\u5148\u672a\u77e5\u7684\u67d0\u4e2a\u4e0b\u6807 k\uff080 <= k < nums.length\uff09\u4e0a\u8fdb\u884c\u4e86 \u65cb\u8f6c\uff0c\u4f7f\u6570\u7ec4\u53d8\u4e3a [nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]]\uff08\u4e0b\u6807 \u4ece 0 \u5f00\u59cb \u8ba1\u6570\uff09\u3002\u4f8b\u5982\uff0c [0,1,2,4,5,6,7] \u5728\u4e0b\u6807 3 \u5904\u7ecf\u65cb\u8f6c\u540e\u53ef\u80fd\u53d8\u4e3a [4,5,6,7,0,1,2] \u3002
<\/em>
<\/em> \u7ed9\u4f60 \u65cb\u8f6c\u540e \u7684\u6570\u7ec4 nums \u548c\u4e00\u4e2a\u6574\u6570 target \uff0c\u5982\u679c nums \u4e2d\u5b58\u5728\u8fd9\u4e2a\u76ee\u6807\u503c target \uff0c\u5219\u8fd4\u56de\u5b83\u7684\u4e0b\u6807\uff0c\u5426\u5219\u8fd4\u56de -1 \u3002
<\/em>
<\/em>
<\/em>
<\/em> \u793a\u4f8b 1\uff1a
<\/em>
<\/em> \u8f93\u5165\uff1anums = [4,5,6,7,0,1,2], target = 0
<\/em> \u8f93\u51fa\uff1a4
<\/em> \u793a\u4f8b 2\uff1a
<\/em>
<\/em> \u8f93\u5165\uff1anums = [4,5,6,7,0,1,2], target = 3
<\/em> \u8f93\u51fa\uff1a-1
<\/em> \u793a\u4f8b 3\uff1a
<\/em>
<\/em> \u8f93\u5165\uff1anums = [1], target = 0
<\/em> \u8f93\u51fa\uff1a-1
<\/em>
<\/em>
<\/em> \u63d0\u793a\uff1a
<\/em>
<\/em> 1 <= nums.length <= 5000
<\/em> -10^4 <= nums[i] <= 10^4
<\/em> nums \u4e2d\u7684\u6bcf\u4e2a\u503c\u90fd \u72ec\u4e00\u65e0\u4e8c
<\/em> \u9898\u76ee\u6570\u636e\u4fdd\u8bc1 nums \u5728\u9884\u5148\u672a\u77e5\u7684\u67d0\u4e2a\u4e0b\u6807\u4e0a\u8fdb\u884c\u4e86\u65cb\u8f6c
<\/em> -10^4 <= target <= 10^4
<\/em>
<\/em>
<\/em> \u8fdb\u9636\uff1a\u4f60\u53ef\u4ee5\u8bbe\u8ba1\u4e00\u4e2a\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(log n) \u7684\u89e3\u51b3\u65b9\u6848\u5417\uff1f
<\/em>
<\/em> * <\/em>@author <\/em><\/strong>zeroheart
<\/em> *
<\/em> *\/
<\/em>public class Question33 {
    public int search(int[] nums, int target) {
        int res = -1;
        int low = 0;
        int high = nums.length - 1;
        int mid = 0;

        while (low <= high) {
            mid = low + (high - low) \/ 2;

            if (nums[mid] == target) {
                return mid;
            }

            \/\/ nums[0] \u662f\u4e00\u4e2a\u5206\u754c\u70b9

            if (nums[0] <= nums[mid]) {
                \/\/ mid \u51fa\u73b0\u5728\u9ad8\u7684\u4e00\u4fa7

                \/\/ \u770btarget\u7684\u60c5\u51b5\uff0c\u79fb\u52a8\u6307\u9488
                if (nums[0] <= target && target < nums[mid]) {
                    \/\/ \u6ce8\u610f\u8fd9\u91cc\u7684<=
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            } else {
                if (nums[mid] < target && target <= nums[nums.length - 1]) {
                    \/\/ \u6ce8\u610f\u8fd9\u91cc\u7684<=
                    low = mid + 1;
                } else {
                    high = mid - 1;
                }
            }
        }

        return res;
    }

}<\/pre>\n\n\n\n
74. \u641c\u7d22\u4e8c\u7ef4\u77e9\u9635<\/a><\/p>\n\n\n\n
\u8fd9\u4e5f\u662f\u4e8c\u5206\u6cd5\u7684\u53d8\u79cd\uff0c\u4e8c\u4f4d\u6570\u7ec4\u7684\u5750\u6807\u8981\u8f6c\u4e00\u4e0b\u3002\u6ce8\u610f\u4e8c\u5206\u7684high = len -1\uff1b<\/p>\n\n\n\n

\/**
<\/em> 74. \u641c\u7d22\u4e8c\u7ef4\u77e9\u9635
<\/em> \u7f16\u5199\u4e00\u4e2a\u9ad8\u6548\u7684\u7b97\u6cd5\u6765\u5224\u65ad m x n \u77e9\u9635\u4e2d\uff0c\u662f\u5426\u5b58\u5728\u4e00\u4e2a\u76ee\u6807\u503c\u3002\u8be5\u77e9\u9635\u5177\u6709\u5982\u4e0b\u7279\u6027\uff1a
<\/em>
<\/em> \u6bcf\u884c\u4e2d\u7684\u6574\u6570\u4ece\u5de6\u5230\u53f3\u6309\u5347\u5e8f\u6392\u5217\u3002
<\/em> \u6bcf\u884c\u7684\u7b2c\u4e00\u4e2a\u6574\u6570\u5927\u4e8e\u524d\u4e00\u884c\u7684\u6700\u540e\u4e00\u4e2a\u6574\u6570\u3002
<\/em>
<\/em>
<\/em> \u793a\u4f8b 1\uff1a
<\/em>
<\/em>
<\/em> \u8f93\u5165\uff1amatrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 3
<\/em> \u8f93\u51fa\uff1atrue
<\/em> \u793a\u4f8b 2\uff1a
<\/em>
<\/em>
<\/em> \u8f93\u5165\uff1amatrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 13
<\/em> \u8f93\u51fa\uff1afalse
<\/em>
<\/em>
<\/em> \u63d0\u793a\uff1a
<\/em>
<\/em> m == matrix.length
<\/em> n == matrix[i].length
<\/em> 1 <= m, n <= 100
<\/em> -104 <= matrix[i][j], target <= 104
<\/em>
<\/em> * <\/em>@author <\/em><\/strong>zeroheart
<\/em> *
<\/em> *\/
<\/em>public class Question74 {

    public boolean searchMatrix(int[][] matrix, int target) {
        \/\/ \u5b9e\u9645\u5c31\u662f\u4e8c\u5206\u6cd5\uff0c\u5c31\u662f\u8981\u505a\u4e00\u6b21\u5750\u6807\u8f6c\u5316
        int m = matrix.length;
        int n = matrix[0].length;

        int low = 0; int high = m * n - 1;
        while (low <= high){
            int mid = low + (high - low) \/ 2;
            int tmp = matrix[mid\/n][mid%n];
            if(tmp == target) return true;
            if(tmp < target) {
                low = mid + 1;
            }else {
                high = mid - 1;
            }
        }
        return false;
    }


}<\/pre>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
34. \u5728\u6392\u5e8f\u6570\u7ec4\u4e2d\u67e5\u627e\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u548c\u6700\u540e\u4e00\u4e2a\u4f4d\u7f6e \u8fd9\u9898\u56de\u987e\u4e00\u4e0b\u4e8c\u5206\u6cd5\uff0c\u8981\u627e\u6700\u5de6\u548c\u6700\u53f3\u7684\u8fb9\u754c\uff0c\u5728mid = t […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[155],"tags":[196],"_links":{"self":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/2697"}],"collection":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2697"}],"version-history":[{"count":9,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/2697\/revisions"}],"predecessor-version":[{"id":2707,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/2697\/revisions\/2707"}],"wp:attachment":[{"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2697"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2697"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zeroheart.xyz\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2697"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}