# Add One to List - Amazon Top Interview Questions

### Problem Statement :

```You are given a list of integers nums, representing a decimal number and nums[i] is between [0, 9].

For example, [1, 3, 9] represents the number 139.

Return the same list in the same representation except modified so that 1 is added to the number.

Constraints

1 ≤ n ≤ 100,000 where n is the length of nums.

Example 1

Input
nums = [1, 9, 1]

Output
[1, 9, 2]

Example 2

Input
nums = [9]

Output
[1, 0]```

### Solution :

```                        ```Solution in C++ :

vector<int> solve(vector<int>& nums) {
if (nums.empty()) return nums;

int i = nums.size() - 1;
while (nums[i] == 9 && i != 0) {
nums[i] = 0;
i--;
}

if (nums.size() == 100000 && nums[i] == 9) return nums;

if (nums[i] == 9) {
nums[i] = 1;
nums.push_back(0);
} else
nums[i] += 1;

return nums;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public int[] solve(int[] nums) {
if (nums[nums.length - 1] < 9) {
nums[nums.length - 1] += 1;
return nums;
}
int[] rtn = new int[nums.length + 1];
int carry = 1;
for (int i = nums.length - 1; i >= 0; i--) {
if (nums[i] < 9) {
nums[i] += carry;
return nums;
} else
nums[i] = 0;
}
rtn[0] = 1;
return rtn;
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, nums):
i = len(nums) - 1
while i >= 0:
if nums[i] + 1 <= 9:
nums[i] = nums[i] + 1
break
else:
nums[i] = 0
i -= 1
if i < 0:
nums.insert(0, 1)
return nums```
```

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## Sparse Arrays

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## Array Manipulation

Starting with a 1-indexed array of zeros and a list of operations, for each operation add a value to each of the array element between two given indices, inclusive. Once all operations have been performed, return the maximum value in the array. Example: n=10 queries=[[1,5,3], [4,8,7], [6,9,1]] Queries are interpreted as follows: a b k 1 5 3 4 8 7 6 9 1 Add the valu

## Print the Elements of a Linked List

This is an to practice traversing a linked list. Given a pointer to the head node of a linked list, print each node's data element, one per line. If the head pointer is null (indicating the list is empty), there is nothing to print. Function Description: Complete the printLinkedList function in the editor below. printLinkedList has the following parameter(s): 1.SinglyLinkedListNode

## Insert a Node at the Tail of a Linked List

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