public int findPeak(int input1, int input2, int[] input3) {
    List<int> peaks = new List<int>();
    for (int i = 0; i < input3.Length; i++) {
        if ((i == 0 || input3[i] >= input3[i - 1]) && 
            (i == input3.Length - 1 || input3[i] >= input3[i + 1])) {
            peaks.Add(input3[i]);
        }
    }
    return input2 <= peaks.Count ? peaks[input2 - 1] : -1;
}

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