Total Sales of Product

In this question you will be given a table as below, where the first row lists the names of products, and each of row after that lists the sales of the product for each day (over some time range).

[
  ["A", "B", "C"],
  [ 2 ,  7 ,  1 ],
  [ 3 ,  6 ,  6 ],
  [ 4 ,  5 ,  5 ]
]

Write a function that receives:

• A sales table sales_table as shown above.
• The name of a product product.

... and returns the total sales if the product is on the list, otherwise return the string "Product not found".

Examples

total_sales([
  ["A", "B", "C"],
  [ 2 ,  7 ,  1 ],
  [ 3 ,  6 ,  6 ],
  [ 4 ,  5 ,  5 ]
], "A") ➞ 9

# 2 + 3 + 4 = 9

total_sales([
  ["A", "B", "C"],
  [ 2 ,  7 ,  1 ],
  [ 3 ,  6 ,  6 ],
  [ 4 ,  5 ,  5 ]
], "C") ➞ 12

# 1 + 6 + 5 = 12

total_sales([
  ["A", "B", "C"],
  [ 2 ,  7 ,  1 ],
  [ 3 ,  6 ,  6 ],
  [ 4 ,  5 ,  5 ]
], "D") ➞ "Product not found"

Notes

The examples above all use the same sales table, but in the tests the table will vary.