import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.NoSuchElementException;

public class Main {

	public static void main(String[] args) {
		new Main().run();
	}
	
	class SegTree {
		int n=1;
		int[] v;
		
		public SegTree(int n_) {
			while (n<n_) n*=2;
			v=new int[2*n-1];
		}
		
		void add(int k,int val) {
			k+=n-1;
			v[k]+=val;
			while (k>0) {
				k=(k-1)/2;
				v[k]=v[2*k+1]+v[2*k+2];
			}
		}
		
		int query(int a,int b) {
			return query(0,n,a,b,0);
		}
		
		int query(int l,int r,int a,int b,int k) {
			if (a<=l&&r<=b) return v[k];
			else if (r<=a||b<=l) return 0;
			else {
				int vl=query(l,(l+r)/2,a,b,2*k+1);
				int vr=query((l+r)/2,r,a,b,2*k+2);
				return vl+vr;
			}
		}
	}
	
	void run() {
		FastScanner sc=new FastScanner();
		int N=sc.nextInt();
		int[] A=new int[N];
		int[] B=new int[N];
		int[] C=new int[N];
		for (int i=0;i<N;++i) {
			A[i]=sc.nextInt()-1;
		}
		for (int i=0;i<N;++i) {
			B[i]=sc.nextInt()-1;
			C[B[i]]=i;
		}
		for (int i=0;i<N;++i) {
			A[i]=C[A[i]];
		}
		int ans=0;
		SegTree seg=new SegTree(N);
		for (int i=0;i<N;++i) {
			ans+=seg.query(A[i], N+1);
			seg.add(A[i], 1);
		}
		System.out.println(ans);
	}
	
	void tr(Object...objects) {System.out.println(Arrays.deepToString(objects));}
	
	
	class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;
	    private boolean hasNextByte() {
	        if (ptr < buflen) {
	            return true;
	        }else{
	            ptr = 0;
	            try {
	                buflen = in.read(buffer);
	            } catch (IOException e) {
	                e.printStackTrace();
	            }
	            if (buflen <= 0) {
	                return false;
	            }
	        }
	        return true;
	    }
	    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
	    private boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
	    private void skipUnprintable() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;}
	    public boolean hasNext() { skipUnprintable(); return hasNextByte();}
	    public String next() {
	        if (!hasNext()) throw new NoSuchElementException();
	        StringBuilder sb = new StringBuilder();
	        int b = readByte();
	        while(isPrintableChar(b)) {
	            sb.appendCodePoint(b);
	            b = readByte();
	        }
	        return sb.toString();
	    }
	    public long nextLong() {
	        if (!hasNext()) throw new NoSuchElementException();
	        long n = 0;
	        boolean minus = false;
	        int b = readByte();
	        if (b == '-') {
	            minus = true;
	            b = readByte();
	        }
	        if (b < '0' || '9' < b) {
	            throw new NumberFormatException();
	        }
	        while(true){
	            if ('0' <= b && b <= '9') {
	                n *= 10;
	                n += b - '0';
	            }else if(b == -1 || !isPrintableChar(b)){
	                return minus ? -n : n;
	            }else{
	                throw new NumberFormatException();
	            }
	            b = readByte();
	        }
	    }
	    public int nextInt() {
	    	return (int)nextLong();
	    }
	}
}