import java.util.Scanner;
import java.util.Arrays;
class Main{
    public static void main(String arg[]){
        Scanner scn=new Scanner(System.in);
        int n = scn.nextInt();
        int m = scn.nextInt();
        int x = scn.nextInt();
        int[] line = new int[n];
        Arrays.fill(line,0);
        for(int i=0;i<m;i++){
            int buf = scn.nextInt();
            line[buf]++;
        }
        int rCost = 0;
        int lCost = 0;
        for(int i=0;i<n;i++){
            if(line[i]==1&&i<x){
                rCost++;
            }else if(line[i]==1){
                lCost++;
            }
        }
        System.out.println(Math.min(rCost,lCost));
    }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz