{"id":9424,"date":"2022-01-17T17:13:22","date_gmt":"2022-01-18T01:13:22","guid":{"rendered":"https:\/\/zxi.mytechroad.com\/blog\/?p=9424"},"modified":"2022-01-17T17:16:52","modified_gmt":"2022-01-18T01:16:52","slug":"leetcode-2134-minimum-swaps-to-group-all-1s-together-ii","status":"publish","type":"post","link":"https:\/\/zxi.mytechroad.com\/blog\/sliding-window\/leetcode-2134-minimum-swaps-to-group-all-1s-together-ii\/","title":{"rendered":"\u82b1\u82b1\u9171 LeetCode 2134. Minimum Swaps to Group All 1’s Together II"},"content":{"rendered":"\n

A swap<\/strong> is defined as taking two distinct<\/strong> positions in an array and swapping the values in them.<\/p>\n\n\n\n

A circular<\/strong> array is defined as an array where we consider the first<\/strong> element and the last<\/strong> element to be adjacent<\/strong>.<\/p>\n\n\n\n

Given a binary<\/strong> circular<\/strong> array nums<\/code>, return the minimum number of swaps required to group all <\/em>1<\/code>‘s present in the array together at any location<\/strong><\/em>.<\/p>\n\n\n\n

Example 1:<\/strong><\/p>\n\n\n\n

Input:<\/strong> nums = [0,1,0,1,1,0,0]\nOutput:<\/strong> 1\nExplanation:<\/strong> Here are a few of the ways to group all the 1's together:\n[0,0,1,1,1,0,0] using 1 swap.\n[0,1,1,1,0,0,0] using 1 swap.\n[1,1,0,0,0,0,1] using 2 swaps (using the circular property of the array).\nThere is no way to group all 1's together with 0 swaps.\nThus, the minimum number of swaps required is 1.\n<\/pre>\n\n\n\n
Example 2:<\/strong><\/p>\n\n\n\n
Input:<\/strong> nums = [0,1,1,1,0,0,1,1,0]\nOutput:<\/strong> 2\nExplanation:<\/strong> Here are a few of the ways to group all the 1's together:\n[1,1,1,0,0,0,0,1,1] using 2 swaps (using the circular property of the array).\n[1,1,1,1,1,0,0,0,0] using 2 swaps.\nThere is no way to group all 1's together with 0 or 1 swaps.\nThus, the minimum number of swaps required is 2.\n<\/pre>\n\n\n\n
Example 3:<\/strong><\/p>\n\n\n\n
Input:<\/strong> nums = [1,1,0,0,1]\nOutput:<\/strong> 0\nExplanation:<\/strong> All the 1's are already grouped together due to the circular property of the array.\nThus, the minimum number of swaps required is 0.\n<\/pre>\n\n\n\n
Constraints:<\/strong><\/p>\n\n\n\n
  • 1 <= nums.length <= 105<\/sup><\/code><\/li>
  • nums[i]<\/code> is either 0<\/code> or 1<\/code>.<\/li><\/ul>\n\n\n\n
    Solution: Sliding Window<\/strong><\/h2>\n\n\n\n
    Step 1: Count how many ones are there in the array. Assume it’s K.
    Step 2: For each window of size k, count how many ones in the window, we have to swap 0s out with 1s to fill the window. ans = min(ans, k – ones).<\/p>\n\n\n\n
    Time complexity: O(n)
    Space complexity: O(1)<\/p>\n\n\n\n
    \n
    C++<\/h2>\n
    \n\n
    \n\/\/ Author: Huahua\nclass Solution {\npublic:\n  int minSwaps(vector& nums) {\n    const int n = nums.size();\n    const int k = accumulate(begin(nums), end(nums), 0);\n    int ans = INT_MAX;\n    for (int i = 0, cur = 0; i < n + k; ++i) {\n      if (i >= k) cur -= nums[(i - k + n) % n];\n      cur += nums[i % n];      \n      ans = min(ans, k - cur);\n    }\n    return ans;\n  }\n};\n<\/pre>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"
    A swap is defined as taking two distinct positions in an array and swapping the values in them. A circular array is defined as an array where we consider the first element and…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[476],"tags":[20,177,215],"class_list":["post-9424","post","type-post","status-publish","format-standard","hentry","category-sliding-window","tag-array","tag-medium","tag-sliding-window","entry","simple"],"_links":{"self":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9424","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/comments?post=9424"}],"version-history":[{"count":2,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9424\/revisions"}],"predecessor-version":[{"id":9427,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/posts\/9424\/revisions\/9427"}],"wp:attachment":[{"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/media?parent=9424"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/categories?post=9424"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zxi.mytechroad.com\/blog\/wp-json\/wp\/v2\/tags?post=9424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}