백준 - 집합의 표현 (1717)

let file = FileIO()
let n = file.readInt(), m = file.readInt()
var arr = Array(0...n)
var answer = ""

for _ in 0..<m {
    let type = file.readInt()
    let a = file.readInt()
    let b = file.readInt()
    
    if type == 0 {
        union(a, b)
    } else {
        if getParents(a, b) {
            answer += "YES\n"
        } else {
            answer += "NO\n"
        }
    }
}

print(answer)

func union(_ a: Int, _ b: Int) {
    let aParent = find(a)
    let bParent = find(b)
    if a < b {
        arr[bParent] = aParent
    } else {
        arr[aParent] = bParent
    }
}

func find(_ num: Int) -> Int {
    if arr[num] == num {
        return num
    }
    arr[num] = find(arr[num])
    return arr[num]
}

func getParents(_ a: Int, _ b: Int) -> Bool {
    let aParent = find(a)
    let bParent = find(b)
    
    return aParent == bParent
}

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