Create 3399.Smallest-Substring-With-Identical-Characters-II.cpp

Author: wisdompeak

Binary_Search/3399.Smallest-Substring-With-Identical-Characters-II/3399.Smallest-Substring-With-Identical-Characters-II.cpp

@@ -0,0 +1,61 @@
+class Solution {
+public:
+ int minLength(string s, int numOps) 
+ {
+ vector<int>arr;
+ vector<int>nums;
+ for (auto ch: s) nums.push_back(ch-'0');
+ 
+ int n = s.size();
+ for (int i=0; i<n;)
+ {
+ int j = i;
+ while (j<n && s[j]==s[i])
+ j++;
+ arr.push_back(j-i);
+ i = j;
+ }
+ 
+ int left = 1, right = n;
+ while (left < right)
+ {
+ int mid = left + (right-left)/2; 
+ if (isOK(arr, nums, mid, numOps))
+ right = mid;
+ else
+ left = mid+1;
+ }
+ return left;
+ }
+ 
+ bool isOK(vector<int>arr, vector<int>&nums, int len, int numOps)
+ {
+ if (len==1)
+ {
+ int count = 0;
+ for (int i=0; i<nums.size(); i++)
+ count += (nums[i]==(i%2));
+ if (count <= numOps)
+ return true;
+ 
+ count = 0;
+ for (int i=0; i<nums.size(); i++)
+ count += (nums[i]!=(i%2));
+ if (count <= numOps)
+ return true;
+ 
+ return false;
+ }
+ 
+ int count = 0;
+ 
+ for (int i=0; i<arr.size(); i++)
+ {
+ int x = arr[i];
+ count += ceil((x-len)*1.0/(len+1));
+ if (count>numOps)
+ return false; 
+ }
+ return true;
+ }
+};