benfletcher/compute-change.md

## compute-change.md

      
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              compute-change.md
            
          
    Compute the number of unique change combinations possible.

You will be given:

an amount of money
an array of coin denominations
you have access to an unlimited number of each coin denomination

For example, there are 3 ways to give change for 4 if you have coins with denomination 1 and 2:
1+1+1+1
1+1+2
2+2

Don't count coins in a different order more than once:
1+1+2 == 2+1+1

Your function should take an amount to change and an array of unique denominations for the coins:
computeChange(4, [1,2])     // => 3
computeChange(10, [5,2,3])  // => 4
computeChange(11, [5,7])    // => 0