# Climbing Stairs

You are climbing a staircase. It takes n steps to reach the top.

Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?

```
class Solution:
def climbStairs(self, n: int) -> int:
if n == 0 or n == 1:
return 1
prev, curr = 1, 1
for i in range(2, n+1):
temp = curr
curr = prev + curr
prev = temp
return curr
```

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