nums = [2,3,1,1,4]

True

i	nums[i]	farthest = max(farthest, i + nums[i])	can reach i?	note
0	2	max(0, 0+2)=2	✅ yes	can go up to index 2
1	3	max(2, 1+3)=4	✅ yes	can go to the end
2	1	max(4, 2+1)=4	✅ yes	still within range
3	1	max(4, 3+1)=4	✅ yes	
4	4	max(4, 4+4)=8	✅ yes	end reached

class Solution:
    def canJump(self, nums: List[int]) -> bool:
        n = len(nums)
        reachable = [False] * n
        reachable[0] = True

        for i in range(n):
            if not reachable[i]:
                continue
            for j in range(1, nums[i] + 1):
                if i + j < n:
                    reachable[i + j] = True
        return reachable[-1]

class Solution:
    def canJump(self, nums: List[int]) -> bool:
        farthest = 0
        for i, jump in enumerate(nums):
            if i > farthest:
                return False
            farthest = max(farthest, i + jump)
        return True