# Palindromic Integer - Amazon Top Interview Questions

### Problem Statement :

```Given a non-negative integer num, return whether it is a palindrome.

Bonus: Can you solve it without using strings?

Constraints

num < 2 ** 31

Example 1

Input
num = 121

Output
True

Example 2

Input
num = 20200202

Output
True

Example 3

Input
num = 43

Output
False```

### Solution :

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

bool solve(int num) {
int t = num;
int rev = 0;
while (t) {
rev = rev * 10 + t % 10;
t = t / 10;
}
if (rev == num) {
return true;
}
return false;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public boolean solve(int num) {
if (num < 0 || (num != 0 && num % 10 == 0))
return false;

int rev = 0;
while (num > rev) {
rev = rev * 10 + num % 10;
num = num / 10;
}
return (num == rev || num == rev / 10);
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, num):
a = 0
c = num
while num > 0:
r = num % 10
num = num // 10
a = (10 * a) + r
if a == c:
return True
else:
return False```
```

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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

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