PythonEasyNumbers10 min

Sum the digits of an integer

Ignore a leading minus sign. The digit sum of zero is zero. Interviewers use this problem to assess use remainder and integer division by ten.

Input

One integer n.

Output

Print the result on one line; print an empty line for an empty string.

Constraints

-10^18 <= n <= 10^18.

Example

Input

Output

Example 2 input

-999999999999999999

Output

All repeated digits must contribute.

Public test cases (2)

Input
```
12345
```
Expected output
```
15
```
Input
```
-908
```
Expected output
```
17
```

Hints (2)

Identify the state needed to avoid repeated work.
Use remainder and integer division by ten.

Target complexity: time O(d), where d is the digit count · space O(1)

Your solution

import sys


def solve_sum_digits(n):
    # your code
    return 0


if __name__ == "__main__":
    data = sys.stdin.read()
    n = int(data)
    result = solve_sum_digits(n)
    print(result)

Standard input

Checking runner availability…

Reference solution

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All Python programs

Sum the digits of an integer

Input

Output

Constraints

Example

Public test cases (2)

Your solution

Reference solution

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