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Day 25 of 30 days Leetcode Challenge - Jump Game

Jump Game

Given an array of non-negative integers, you are initially positioned at the first index of the array.

Each element in the array represents your maximum jump length at that position.

Determine if you are able to reach the last index.

Example 1:

Input: [2,3,1,1,4]
Output: true
Explanation: Jump 1 step from index 0 to 1, then 3 steps to the last index.

Example 2:

Input: [3,2,1,0,4]
Output: false
Explanation: You will always arrive at index 3 no matter what. Its maximum
             jump length is 0, which makes it impossible to reach the last index.

Solution

It's simple straight forward solution.

class Solution {
    func canJump(_ nums: [Int]) -> Bool {        
        var byFar: Int = 0
        for i in 0..<nums.count {
            if nums[i] == 0 || i > byFar  {
                continue
            }
            byFar = max(byFar, i + nums[i])
        }    
        
        return byFar >= nums.count - 1
    }
    
}

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