#include <bits/stdc++.h>
using namespace std;
 
int KthSmallest(vector<int>& arr, int k) {
    sort(arr.begin(), arr.end());
 
    int uniqueCount = 0;
    int lastUnique = INT_MIN;
 
    for (int i = 0; i < arr.size(); ++i) {
        if (arr[i] != lastUnique) {
            uniqueCount++;
            lastUnique = arr[i];
        }
        if (uniqueCount == k) {
            return arr[i];
        }
    }
    return -1; 
}
 
 
int main() {
 
    vector<int> arr = {10, 20, 7, 8, 7, 7, 6} ;
    int ans = KthSmallest(arr, 3);
    cout<<ans<<endl;
 
    return 0;
}

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