find the intersection of two maps in swift

One way to find the intersection of two maps (dictionaries) in Swift is by converting each map into a set of key-value pairs and then using the intersection method of sets to get the common elements. Here's an example code snippet:

main.swift
let map1 = ["a": 1, "b": 2, "c": 3]
let map2 = ["b": 20, "c": 30, "d": 40]

let set1 = Set(map1)
let set2 = Set(map2)

let intersection = set1.intersection(set2)

// Alternatively, you can use the filter method on the first map:
// let intersection = map1.filter { set2.contains($0) }

let result = Dictionary(uniqueKeysWithValues: intersection)

print(result) // Output: ["c": 3, "b": 2]
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In this example, we first create two dictionaries (map1 and map2) with some overlapping keys. We then convert each dictionary into a set of key-value pairs using the Set initializer. Finally, we use the intersection method of sets to get the common elements, which gives us a set of tuples with the key-value pairs that exist in both maps. We create a new dictionary from this set using the Dictionary initializer, and print the result.

Note that in the case of overlapping keys, the value from the first map (map1 in this example) is used in the result. If you want to use the value from the second map instead, you can change the order of the sets or modify the code accordingly.