sum-of-multiples

Sum of Multiples

Find the sum of all multiples of n below m

Keep in Mind

• n and m are natural numbers (positive integers)
• m is excluded from the multiples

Examples

Kata.sumMul(2, 9)   ==> 2 + 4 + 6 + 8 = 20
Kata.sumMul(3, 13)  ==> 3 + 6 + 9 + 12 = 30
Kata.sumMul(4, 123) ==> 4 + 8 + 12 + ... = 1860
Kata.sumMul(4, -7)  // throws IllegalArgumentException