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# Reverse Integer InterviewBit Solution

Problem Description:

Reverse digits of an integer.

Example1:

x = 123,
return 321

Example2:

x = -123,
return -321

Return 0 if the result overflows and does not fit in a 32 bit signed integer

## Approach

The approach is to extract the last digit of the number and push it to another number at the unit place.

For example, N = 123
Take R = 0    // To store reverse number.

Iteration 1:
Last_Digit = N % 10 = 3
N = N / 10 = 12
R = (R * 10) + Last_Digit = 0 + 3 = 3

Iteration 2:
Last_Digit = N % 10 = 2
N = N / 10 = 1
R = (R * 10) + Last_Digit = 30 + 2 = 32

Iteration 3:
Last_Digit = N % 10 = 1
N = N / 10 = 0
R = (R * 10) + Last_Digit = 320 + 1 = 321

Iteration 4:
N == 0; STOP;

## Time & Space Complexity:

Time Complexity: O(N), N is the number of digits
Space Complexity: O(1)

Code in C++

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