computes a kind of sum from the values specified by the value_range
None
There is no guarantee in which order the values will be reduced (folded).
So the the reduction function must obey to the law of assosiativity!
| std::reduce | computes a kind of sum from the items of a collection |
| std::map | applies a function to all items of a collection |
| std::map_reduce | combines a map and a reduce operation into a single operation |