[Kata] Clojure - Day 28

Sum of a sequence

our task is to make function, which returns the sum of a sequence of integers. The sequence is defined by 3 non-negative values: begin, end, step. If begin value is greater than the end, function should returns 0.

Example

sequenceSum(2,2,2) === 2
sequenceSum(2,6,2) === 12 // 2 + 4 + 6
sequenceSum(1,5,1) === 15 // 1 + 2 + 3 + 4 + 5
sequenceSum(1,5,3) === 5 // 1 + 4

Solution

const sequenceSum = (begin, end, step) => {
  if (begin > end) {
    return 0;
  }
  return begin + sequenceSum(begin + step, end, step);
};