The Stamina Trail

A hiker travels a path of N points with elevations E[0...N-1]. Starting at point 0 with S stamina, the hiker wants to reach point N-1. - Moving from i to i+1: costs 2*(E[i+1]-E[i]) stamina if ascending, or 1 stamina if flat or descending. - Shortcut: From any i, the hiker can 'leap' to i+2. This always costs a flat K stamina regardless of elevation. Find the minimum stamina required to reach the end point N-1. Input Format: Line 1: N S K Line 2: N integers (elevations E) Output Format: A single integer (min stamina) or -1 if impossible to reach with S stamina. Example: Input: 4 10 5 10 12 11 15 Output: 9 Explanation: 0->1 costs 2*(12-10)=4. 1->3 (leap) costs 5. Total 9.