824. Stairs to Heaven
Arjun is preparing to ascend the celestial staircase. The staircase has N steps leading to heaven. Arjun can choose to climb either one step or two steps at a time. Determine the number of unique ways in which Arjun can reach heaven.
The first line of input consists of an integer N, representing the number of steps in the staircase.
Print the number of distinct ways in which Arjun can climb to heaven.
1 <= n <= 45