import java.util.Scanner;
// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int a = in.nextInt();
int b = in.nextInt();
String n = in.nextLine();
String str1 = in.nextLine();
String str2 = in.nextLine();
String[] strArray1 = str1.split(" ");
String[] strArray2 = str2.split(" ");
int[] intArray1 = new int[strArray1.length];
int[] intArray2 = new int[strArray2.length];
for(int i = 0 ; i < strArray1.length; i++){
intArray1[i] = Integer.parseInt(strArray1[i]);
}
for(int i = 0 ; i < strArray2.length; i++){
intArray2[i] = Integer.parseInt(strArray2[i]);
}
int res = 0;
for(int i = 0; i < strArray1.length; i++){
res += Math.min(intArray1[i], intArray2[i]);
}
res = Math.min(res, b);
System.out.println(res);
}
}