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#include <iostream>
#include <vector>
#include <algorithm>

class Solution {
public:
    int maxDistance(std::vector<int>& position, int m) {
        std::sort(position.begin(), position.end());
        int n = position.size();
        int left = 1, right = (position.back() - position[0]) / (m - 1);
        while (right >= left) {
            int mid = (right + left) / 2;
            if (check(position, m, n, mid)) {
                left = mid + 1;
            }
            else {
                right = mid - 1;
            }
        }
        return right;
    }
    
private:
    bool check(std::vector<int>& position, int m, int n, int dist) {
        int prev = 0;
        for (int i = 1; i < n; ++i) {
            if (position[i] - position[prev] >= dist) {
                --m;
                if (m == 1) {
                    return true;
                }
                prev = i;
            }
        }
        return false;
    }
};