Maximum Building Height.cpp

class Solution {
public:
    int maxBuilding(int n, vector<vector<int>>& restrictions) {
        restrictions.push_back({1, 0});
        restrictions.push_back({n, n-1}); 
        sort(restrictions.begin(), restrictions.end()); 
        for (int i = restrictions.size()-2; i >= 0; --i) {
            restrictions[i][1] = min(restrictions[i][1], restrictions[i+1][1] + restrictions[i+1][0] - restrictions[i][0]); 
        }
        
        int ans = 0; 
        for (int i = 1; i < restrictions.size(); ++i) {
            restrictions[i][1] = min(restrictions[i][1], restrictions[i-1][1] + restrictions[i][0] - restrictions[i-1][0]); 
            ans = max(ans, (restrictions[i-1][1] + restrictions[i][0] - restrictions[i-1][0] + restrictions[i][1])/2); 
        }
        return ans; 
    }
};