1642

class Solution {
public:
    int furthestBuilding(vector<int>& heights, int bricks, int ladders) {
        priority_queue<int, vector<int>, greater<int>> pq;

        for(int i=0; i<heights.size()-1; i++){
            // Get next climb height.
            int climb = heights[i+1]-heights[i];

            // If it is down jump, continue.
            if(climb <= 0) continue;

            // Assign a ladder to it.
            pq.push(climb);
            if(pq.size() <= ladders) continue;

            // If ladders are over, assign bricks to smallest ladder so far.
            int lastClimb = pq.top();
            pq.pop();
            bricks -= lastClimb;
            if(bricks <  0) return i;
        }
        return heights.size()-1;
    }
};