jump-game-55.go

/*
You are given an integer array nums. You are initially positioned at the array's first index, and each element in the array represents your maximum jump length at that position.

Return true if you can reach the last index, or false otherwise.


Example 1:

Input: nums = [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: nums = [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.
 

Constraints:

1 <= nums.length <= 104
0 <= nums[i] <= 105
*/

func canJump(nums []int) bool {
    highestIndex := 0

    // Iterate through each item in the slice
    for idx, val := range nums {
        // Is the length of the slice 1?
        if len(nums) == 1 || idx == len(nums) - 1 {
            return true
        } else if val > 0 && idx < len(nums) - 1 { 
            // Set highest possible index
            if (idx + nums[idx]) > highestIndex {
                highestIndex = idx + nums[idx]
            }
            // Do I have possible jumps?
            // Iterate through the possible jumps
            for i := 1; i <= nums[idx]; i++ {
                // Do I reach the end of the slice?
                if (idx + i) >= len(nums) - 1 {
                    return true
                }
            }
        } else if val == 0 && idx < len(nums) - 1 && highestIndex <= idx  {
            // If no possible jumps and we're not at the end of the slice
            return false
        }
    }

    return false
}

/*
func canJump(nums []int) bool {
    isPossible := true

    if len(nums) > 1 {
        for i := 0; i <= len(nums) - 2; i++ {
            for j := nums[i]; j >= 0; j-- {
                if i != 0 && nums[i] == 0 && nums[i-1] < 2 {
                    jumpsToPass := 0
                    for k := 0; k < i; k++ {
                        jumpsToPass += nums[k]
                    }
                    if jumpsToPass <= i {
                        isPossible = false
                        break
                    }
                }
            }
        }
    }

    if nums[0] == 0 && len(nums) > 1 {
        isPossible = false
    }

    return isPossible
}
*/