import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	}

} Main public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	} main {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int t = sc.nextInt(); t sc.nextInt() sc.nextInt sc int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc double[] doubleArray = new double[n]; doubleArray new double[n] n for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		} int i=0; int i=0; i 0 i < n i n i++ i++ i {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		} {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		} int s = sc.nextInt(); s sc.nextInt() sc.nextInt sc double result = a - (t - (s * 0.006)); result a - (t - (s * 0.006)) a (t - (s * 0.006)) t (s * 0.006) s 0.006 result = result * result result result * result result result doubleArray[i] = result doubleArray[i] doubleArray i result double min = doubleArray[0]; min doubleArray[0] doubleArray 0 int result2 = 0; result2 0 for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		} int i=0; int i=0; i 0 i<doubleArray.length i doubleArray.length doubleArray doubleArray.length i++ i++ i {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		} {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		} if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			} min > doubleArray[i] min doubleArray[i] doubleArray i {	
				min = doubleArray[i];	
				result2 = i;
			} min = doubleArray[i] min doubleArray[i] doubleArray i result2 = i result2 i System.out.println(result2 + 1) System.out.println System.out System System.out result2 + 1 result2 1 String[] args args public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	}

} public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int t = sc.nextInt();
		int a = sc.nextInt();
		
		double[] doubleArray = new double[n];
	
		for(int i=0; i < n; i++) {
		    int s = sc.nextInt();
		    double result = a - (t - (s * 0.006));
		    result = result * result;
		    doubleArray[i] = result;
		}
		
		double min = doubleArray[0];	
		int result2 = 0;
		for (int i=0; i<doubleArray.length; i++) {
			if (min > doubleArray[i]) {	
				min = doubleArray[i];	
				result2 = i;
			}
		}
		System.out.println(result2 + 1);
	}

}
