#include <iostream> 
#include <unordered_map>
#include <vector>
 
 
using namespace std;
 
bool hasNearbyDuplicate(const vector<int>& a, int k) {
    unordered_map<int,int> last; 
    for (int i = 0; i < (int)a.size(); ++i) {
        auto it = last.find(a[i]);
        if (it != last.end() && i - it->second <= k) return true;
        last[a[i]] = i;
    }
    return false;
}
 
int main() {
    vector<int> arr = {1,2,3,1,5};
    int k = 3;
    cout << (hasNearbyDuplicate(arr, k) ? "Yes" : "No") << "\n";
}
 

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