Hoppable - Amazon Top Interview Questions
Problem Statement :
Given an integer list nums where each number represents the maximum number of hops you can make, determine whether you can reach to the last index starting at index 0. Constraints n ≤ 100,000 where n is the length of nums. Example 1 Input nums = [1, 0, 0, 0] Output False Example 2 Input nums = [2, 4, 0, 1, 0] Output True Explanation We can jump from index 0 to 1, and then jump to the end. Example 3 Input nums = [1, 1, 0, 1] Output False Explanation We can't go past index 2 of the array.
Solution :
Solution in C++ :
bool solve(vector<int>& nums) {
int last = nums.size() - 1;
for (int i = nums.size() - 1; i >= 0; --i) {
if (i + nums[i] >= last) last = i;
}
return last == 0;
}
Solution in Java :
import java.util.*;
class Solution {
public boolean solve(int[] nums) {
int reach = 0;
for (int i = 0; i < nums.length; i++) {
if (i > reach) {
return false;
}
reach = Math.max(reach, i + nums[i]);
}
return true;
}
}
Solution in Python :
class Solution:
def solve(self, nums):
n = len(nums)
reach = 0
for i, num in enumerate(nums):
if i > reach:
return False
reach = max(reach, i + nums[i])
if reach >= n - 1:
return True
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