10801. Sum of digits

Given a positive integer n. Find the sum of its digits.

Input. The first line contains the number of test cases t (t < 100). Each of the following t lines contains a number n (1 ≤ n ≤ 10⁵⁰), for which the sum of digits needs to be computed.

Output. Print t lines, each containing the sum of digits of the corresponding number.

Sample input	Sample output
3 123 43 78903	6 7 27

SOLUTION

elementary problem

Algorithm analysis

Since the input numbers can be very large (up to 50 digits), read them as strings. Let s be a string containing the number. For example, if s = “123”, the digit at the i-th position of the number will be s[i] – ‘0’. Sum the digits of the number at all positions.

Algorithm implementation

Read the number of test cases n.

cin >> n;

Process n test cases sequentially.

for (i = 0; i < n; i++)

{

Read the input number into the string s.

cin >> s;

Compute the sum of the digits of the number in the variable sum.

sum = 0;

for (j = 0; j < s.size(); j++)

sum = sum + s[j] - '0';

Print the answer.

cout << sum << endl;

}

Python implementation

Read the number of test cases n.

tests = int(input())

Process n test cases sequentially.

for _ in range(tests):

Read the number as a string. Convert the input string into a list of digits.

lst = list(map(int,input()))

The sum of the numbers in the list lst is equal to the sum of the digits of the current number. Print the result.

print(sum(lst))