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#include <iostream>
#include <cstring>
#include <set>

class Solution {
public:
    int minLength(std::string s, int numOps) {
        int cnt0 = 0, cnt1 = 0, k = 0;
        for (char c : s) {
            k = 1 - k;
            if (k == c - '0') {
                ++cnt0;
            }
            else {
                ++cnt1;
            }
        }
        if (cnt0 <= numOps || cnt1 <= numOps) {
            return 1;
        }
        
        int n = s.length();
        int left = 2, right = n;
        for (int mid = (left + right) / 2; right >= left; ) {
            if (check(s, numOps, mid)) {
                right = mid - 1;
            }
            else {
                left = mid + 1;
            }
            mid = (left + right) / 2;
        }
        return left;
    }
    
private:
    int check(std::string& s, int numOps, int sublen) {
        int curlen = 0;
        char prev = s[0];
        for (char c : s) {
            if (c == prev) {
                ++curlen;
            }
            else {
                numOps -= curlen / (sublen + 1);
                curlen = 1;
                prev = c;
            }
        }
        numOps -= curlen / (sublen + 1);
        return numOps >= 0;
    }
};