Anna has a home robot. She sent it to the store and provided with a list of purchases in the form of a Map with key as the name of the product and value as the number of items to be purchased. However, later Anna decided to send an additional list of purchases (another Map) to the robot.
Write a function helpingTheRobot that combines the two purchase lists into one and returns it as the result. If both lists contain the same product, its quantity in the final MutableMap must be the total value from both lists.
Tip: You can just use the addition operator: map[key] = a + b
Input: purchases: Map<String, Int>, addition: Map<String, Int>
Output: resulting MutableMap<String, Int>.
Sample Input:
purchases: {"bread" to 1, "potatoes" to 7, "milk" to 2}
addition: {"milk" to 1, "water" to 3}
Sample Result:
{bread=1, potatoes=7, milk=3, water=3}
