Vasya has two arrays A and B of lengths n and m, respectively.

He can perform the following operation arbitrary number of times (possibly zero): he takes some consecutive subsegment of the array and replaces it with a single element, equal to the sum of all elements on this subsegment. For example, from the array [1, 10, 100, 1000, 10000] Vasya can obtain array [1, 1110, 10000], and from array [1, 2, 3] Vasya can obtain array [6].

Two arrays A and B are considered equal if and only if they have the same length and for each valid i A_i = B_i.

Vasya wants to perform some of these operations on array A, some on array B, in such a way that arrays A and B become equal. Moreover, the lengths of the resulting arrays should be maximal possible.

Help Vasya to determine the maximum length of the arrays that he can achieve or output that it is impossible to make arrays A and B equal.

Input

The first line contains a single integer n~(1 ≤ n ≤ 3 ⋅ 10^5) — the length of the first array.

The second line contains n integers a_1, a_2, ⋅⋅⋅, a_n~(1 ≤ a_i ≤ 10^9) — elements of the array A.

The third line contains a single integer m~(1 ≤ m ≤ 3 ⋅ 10^5) — the length of the second array.

The fourth line contains m integers b_1, b_2, ⋅⋅⋅, b_m~(1 ≤ b_i ≤ 10^9) - elements of the array B.

Output

Print a single integer — the maximum length of the resulting arrays after some operations were performed on arrays A and B in such a way that they became equal.

If there is no way to make array equal, print "-1".

Examples

Input

5
11 2 3 5 7
4
11 7 3 7


Output

3


Input

2
1 2
1
100


Output

-1


Input

3
1 2 3
3
1 2 3


Output

3
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Random;
import java.util.Stack;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.TreeSet;

public class hacker49 {

	static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
	public static void main(String[] args) {
		OutputStream outputStream =System.out;
	    PrintWriter out =new PrintWriter(outputStream);
		FastReader s=new FastReader();
int n=s.nextInt();
long h1=0;
long h2=0;
long[] a=new long[n+1];
for(int i=1;i<=n;i++) {
	a[i]=s.nextLong();
h1+=a[i];
}

int m=s.nextInt();
long[] b=new long[m+1];
for(int i=1;i<=m;i++) {
	b[i]=s.nextLong();
h2+=b[i];
}	
if(h1!=h2) {
	out.println(-1);
}else {
int i=1;
int j=1;
int pos=0;
while(i<=n && j<=m) {
//	out.println(i+" "+j+" "+pos);
	if(a[i]==b[j]) {
		pos++;
		i++;
		j++;
	}else {
		long sum1=0;
		long sum2=0;
//				if(sum1<sum2) {
//					i++;
//				}else {
//					j++;
//				}
		while(((sum1!=sum2 ) || (sum1==sum2 && sum1==0))) {
//			out.println(sum1+" "+sum2);
			if(sum1<sum2) {
//				i++;
				sum1+=a[i];
				i++;
			}else {
//				j++;
				sum2+=b[j];
			j++;
			}
			if(i>n && j>m) {
				break;
			}
		}
		if(sum1==sum2) {
		pos++;}
//		out.println(i+" "+j);
	}
}
//int pos1=0;
//i=n;
//j=m;
//while(i>=1 && j>=1) {
////	out.println(i+" "+j);
//	if(a[i]==b[j]) {
//		pos1++;
//		i--;
//		j--;
//	}else {
//		long sum1=0;
//		long sum2=0;
////				if(sum1<sum2) {
////					i++;
////				}else {
////					j++;
////				}
//		while((i>=1 || j>=1) && ((sum1!=sum2 ) || (sum1==sum2 && sum1==0))) {
////			out.println(sum1+" "+sum2);
//			if(sum1<sum2) {
////				i++;
//				sum1+=a[i];
//				i--;
//			}else {
////				j++;
//				sum2+=b[j];
//			j--;
//			}
//		}
//		if(sum1==sum2) {
//		pos1++;}
////		out.println(i+" "+j);
//	}
//}
//pos=Math.max(pos, pos1);
out.println(pos>0?pos:-1);
}
out.close();
	}
	static long[] res=new long[200001];
	static long[] giv=new long[200001];
	static int[] par=new int[200001];
	static int[] ans=new int[200001];
	static int[] deg=new int[200001];
	static ArrayList<Integer>[] f1=new ArrayList[200001];
	static int[] vis1=new int[200001];
	static void sf(int[] arr){
        int n = arr.length;
        Random rnd = new Random();
        for(int i=0; i<n; ++i){
            int tmp = arr[i];
            int randomPos = i + rnd.nextInt(n-i);
            arr[i] = arr[randomPos];
            arr[randomPos] = tmp;
        }   
}
	static long ans1=0;
	static boolean u=true; 
	static void dfs1(int node,long prevsum) {
		if(giv[node]<prevsum) {
			u=false;
		}
		if(deg[node]==1 && node!=1) {
			ans1+=(giv[node]-giv[1]);
		}
		vis1[node]=1;
		res[node]=giv[node]-prevsum;
		for(int i=0;i<f1[node].size();i++) {
			if(vis1[f1[node].get(i)]==0) {
				dfs1(f1[node].get(i),giv[node]);
			}
		}
		
	}
	public static int upper_bound(long[] a ,long x,int n) {
		int l=-1;
		int r=n;
		while(r>l+1) {
			int mid=(l+r)/2;
			if(a[mid]<x) {
				l=mid;
			}else {
				r=mid;
			}
		}
		return r;
				
	}
	public static int lower_bound(long[] a ,long x,int n) {
		int l=-1;
		int r=n;
		while(r>l+1) {
			int mid=(l+r)/2;
			if(a[mid]<=x) {
				l=mid;
			}else {
				r=mid;
			}
		}
		return l;
				
	}
	
	static int[] t=new int[501];
	static class pair implements Comparable<pair>{
		private long a;
		private long b;
//		private int c;
		pair(long a,long b){
			this.a=a;
			this.b=b;
//			this.c=c;
		}
		public int compareTo(pair o) {
			return Long.compare(this.a,o.a);
		}
	}
	public static long[] merge_sort(long[] A, int start, int end) {
		if (end > start) {
			int mid = (end + start) / 2;
			long[] v = merge_sort(A, start, mid);
			long[] o = merge_sort(A, mid + 1, end);
			return (merge(v, o));
		} else {
			long[] y = new long[1];
			y[0] = A[start];
			return y;
		}
	}
	public static long[] merge(long a[], long b[]) {
//		int count=0;
		long[] temp = new long[a.length + b.length];
		int m = a.length;
		int n = b.length;
		int i = 0;
		int j = 0;
		int c = 0;
		while (i < m && j < n) {
			if (a[i] < b[j]) {
				temp[c++] = a[i++];
			
			} else {
				temp[c++] = b[j++];
			}
		}
		while (i < m) {
			temp[c++] = a[i++];
		}
		while (j < n) {
			temp[c++] = b[j++];
		}
		return temp;
	}
static ArrayList<Integer>[] f=new ArrayList[501];	
static int[] vis=new int[501];	
static PriorityQueue<pair> e1=new PriorityQueue<>();
static PriorityQueue<pair> e2=new PriorityQueue<>();
static void dfs(int node) {
		vis[node]=1;
//		e2.add(new pair(node));
//		e1.add(new pair(t[node]));
		for(int i=0;i<f[node].size();i++) {
			if(vis[f[node].get(i)]==0) {
				dfs(f[node].get(i));
			}
		}
	}
	
	public static int[] Create(int[] a,int n) {
		int[] b=new int[n+1];
		for(int i=1;i<=n;i++) {
			int j=i;
			int h=a[i];
			while(i<=n) {
				b[i]+=h;
				i=get_next(i);
			}
			i=j;
		}
		return b;
	}
public static int get_next(int a) {
	return a+(a&-a);
}
public static int get_parent(int a) {
	return a-(a&-a);
}
public static int query_1(int[] b,int index) {
	int sum=0;
	if(index<=0) {
		return 0;
	}
	while(index>0) {
		sum+=b[index];
		index=get_parent(index);
	}
	return sum;
}
public static int query(int[] b,int n,int l,int r) {
	int sum=0;
	sum+=query_1(b,r);
	sum-=query_1(b,l-1);
	return sum;
}
public static void update(int[] a,int[] b,int n,int index,int val) {
	int diff=val-a[index];
	a[index]+=diff;
	while(index<=n) {
		b[index]+=diff;
		index=get_next(index);
	}	
}
	
//	public static void Create(int[] a,pair[] segtree,int low,int high,int pos) {
//		if(low>high) {
//			return;
//		}
//		if(low==high) {
//			segtree[pos].b.add(a[low]);
//			return ;
//		}
//		int mid=(low+high)/2;
//		Create(a,segtree,low,mid,2*pos);
//		Create(a,segtree,mid+1,high,2*pos+1);
//		segtree[pos].b.addAll(segtree[2*pos].b);
//		segtree[pos].b.addAll(segtree[2*pos+1].b);
//	}
//	public static void update(pair[] segtree,int low,int high,int index,int pos,int val,int prev) {
//		if(index>high || index<low) {
//			return ;
//		}
//		if(low==high && low==index) {
//			segtree[pos].b.remove(prev);
//			segtree[pos].b.add(val);
//			return;
//		}
//			int mid=(high+low)/2;
//			 update(segtree,low,mid,index,2*pos,val,prev);
//			 update(segtree,mid+1,high,index,2*pos+1,val,prev);
//			 segtree[pos].b.clear();
//			  segtree[pos].b.addAll(segtree[2*pos].b);
//			  segtree[pos].b.addAll(segtree[2*pos+1].b);
//			  
//	}
//	public static pair query(pair[] segtree,int low,int high,int qlow,int qhigh ,int pos) {
//		if(low>=qlow && high<=qhigh) {
//			return segtree[pos];
//		}
//		if(qhigh<low || qlow>high) {
//			return new pair();
//		}
//		int mid=(low+high)/2;
//	  pair a1=query(segtree,low,mid,qlow,qhigh,2*pos);
//	  pair a2=query(segtree,mid+1,high,qlow,qhigh,2*pos+1);
//	  pair a3=new pair();
//	  a3.b.addAll(a1.b);
//	  a3.b.addAll(a2.b);
//	  return a3;
//	  
//	}
//	
//	public static int nextPowerOf2(int n) 
//	{ 
//	    n--; 
//	    n |= n >> 1; 
//	    n |= n >> 2; 
//	    n |= n >> 4; 
//	    n |= n >> 8; 
//	    n |= n >> 16; 
//	    n++;     
//	    return n; 
//	} 
//	
////	static class pair implements Comparable<pair>{
////		private int a;
////		private long b;
//////		private long c;
////		pair(int a,long b){
////			this.a=a;
////			this.b=b;
//////			this.c=c;
////		}
////		public int compareTo(pair o) {
//////		if(this.a!=o.a) {
//////			return Long.compare(this.a, o.a);
//////		}else {
////			return Long.compare(o.b,this.b);
//////		}
////		}
////	}
//	static class pair implements Comparable<pair>{
//		private int a;
//		private int b;
//		pair(int a,int b){
////			this.b=new HashSet<>();
//			this.a=a;
//			this.b=b;
//		}
//		public int compareTo(pair o) {
//			return Integer.compare(this.b, o.b);
//		}
//	}
	public static int lower_bound(ArrayList<Long> a ,int n,long x) {
		int l=0;
		int r=n;
		while(r>l+1) {
			int mid=(l+r)/2;
			if(a.get(mid)<=x) {
				l=mid;
			}else {
				r=mid;
			}
		}
		return l;		
	}

	public static int[] is_prime=new int[1000001];
	public static ArrayList<Long> primes=new ArrayList<>();
 	public static void sieve() {
		long maxN=1000000;
		for(long i=1;i<=maxN;i++) {
			is_prime[(int) i]=1;
		}
		is_prime[0]=0;
		is_prime[1]=0;
		for(long i=2;i*i<=maxN;i++) {
			if(is_prime[(int) i]==1) {
//				primes.add((int) i);
				for(long j=i*i;j<=maxN;j+=i) {
					is_prime[(int) j]=0;
				}
			}
		}
		for(long i=0;i<=maxN;i++) {
			if(is_prime[(int) i]==1) {
				primes.add(i);
			}
		}		
	}
	
	
//	public static pair[] merge_sort(pair[] A, int start, int end) {
//		if (end > start) {
//			int mid = (end + start) / 2;
//			pair[] v = merge_sort(A, start, mid);
//			pair[] o = merge_sort(A, mid + 1, end);
//			return (merge(v, o));
//		} else {
//			pair[] y = new pair[1];
//			y[0] = A[start];
//			return y;
//		}
//	}
//	public static pair[] merge(pair a[], pair b[]) {
//		pair[] temp = new pair[a.length + b.length];
//		int m = a.length;
//		int n = b.length;
//		int i = 0;
//		int j = 0;
//		int c = 0;
//		while (i < m && j < n) {
//			if (a[i].b >= b[j].b) {
//				temp[c++] = a[i++];
//			
//			} else {
//				temp[c++] = b[j++];
//			}
//		}
//		while (i < m) {
//			temp[c++] = a[i++];
//		}
//		while (j < n) {
//			temp[c++] = b[j++];
//		}
//		return temp;
//	}
	
	
//	public static long im(long a) {
//		return binary_exponentiation_1(a,mod-2)%mod;
//	}
	public static double bn1(double a,double n) {
		double res=1;
		while(n>0) {
			if(n%2!=0) {
//				res=((res)%(1000000007) * (a)%(1000000007))%(1000000007);
				res=(res*a);
				n--;
			}else {
//				a=((a)%(1000000007) *(a)%(1000000007))%(1000000007);
				a=(a*a);
				n/=2;
			}
		}
		return (res);
		
	}

	public static long bn(long a,long n) {
		long res=1;
		while(n>0) {
			if(n%2!=0) {
				res=res*a;
				n--;
			}else {
				a*=a;
				n/=2;
			}
		}
		return res;
		
	}

	public static long[] fac=new long[100001];
	public static void find_factorial() {
		fac[0]=1;
		fac[1]=1;
		for(int i=2;i<=100000;i++) {
			fac[i]=(fac[i-1]*i)%(mod);
		}
	}
	
	static long mod=1000000007;
	public static long GCD(long a,long b) {
		if(b==(long)0) {
			return a;
		}
		return GCD(b , a%b);
	}
	static long c=0;
	
		
	
}