On Children's Day, the child got a toy from Delayyy as a present. However, the child is so naughty that he can't wait to destroy the toy.

The toy consists of n parts and m ropes. Each rope links two parts, but every pair of parts is linked by at most one rope. To split the toy, the child must remove all its parts. The child can remove a single part at a time, and each remove consume an energy. Let's define an energy value of part i as vi. The child spend vf1 + vf2 + ... + vfk energy for removing part i where f1, f2, ..., fk are the parts that are directly connected to the i-th and haven't been removed.

Help the child to find out, what is the minimum total energy he should spend to remove all n parts.

Input

The first line contains two integers n and m (1 ≤ n ≤ 1000; 0 ≤ m ≤ 2000). The second line contains n integers: v1, v2, ..., vn (0 ≤ vi ≤ 105). Then followed m lines, each line contains two integers xi and yi, representing a rope from part xi to part yi (1 ≤ xi, yi ≤ n; xi ≠ yi).

Consider all the parts are numbered from 1 to n.

Output

Output the minimum total energy the child should spend to remove all n parts of the toy.

Examples

Input

4 3
10 20 30 40
1 4
1 2
2 3


Output

40


Input

4 4
100 100 100 100
1 2
2 3
2 4
3 4


Output

400


Input

7 10
40 10 20 10 20 80 40
1 5
4 7
4 5
5 2
5 7
6 4
1 6
1 3
4 3
1 4


Output

160

Note

One of the optimal sequence of actions in the first sample is:

  * First, remove part 3, cost of the action is 20. 
  * Then, remove part 2, cost of the action is 10. 
  * Next, remove part 4, cost of the action is 10. 
  * At last, remove part 1, cost of the action is 0. 



So the total energy the child paid is 20 + 10 + 10 + 0 = 40, which is the minimum.

In the second sample, the child will spend 400 no matter in what order he will remove the parts.
	import java.util.*;
	import java.io.*;

			public class codeforces
			{	
				public static long M = 1000000007;
				public static TreeSet<Integer> adj[];
				
				public static void main(String[] args)
				{
					InputReader in = new InputReader(System.in);
					PrintWriter pw = new PrintWriter(System.out);
					
					int n = in.nextInt();
					int m = in.nextInt();
					int[] v = new int[n+1];
					HashMap<Integer, Integer> map = new HashMap<>();
					for(int i=1;i<=n;i++)
						v[i] = in.nextInt();
					adj = new TreeSet[n+1];
					for(int i=0;i<n+1;i++)
						adj[i] = new TreeSet<>();
					for(int i=0;i<m;i++)
					{
						int x = in.nextInt();
						int y = in.nextInt();
						adj[x].add(y);
						adj[y].add(x);
					}
					for(int i=1;i<=n;i++)
					{
						int sum = 0;
						for(int u : adj[i])
							sum += v[u];
						map.put(i, sum);
					}
					int ans = 0;
					for(int i=0;i<n;i++)
					{
						int index = 0, max = 0;
						for(int u : map.keySet())
						{
							if(v[u] > max)
							{
								max = v[u];
								index = u;
							}
						}
						if(map.containsKey(index))
							ans += map.get(index);
						//pw.println(map+" "+max);
						for(int j=1;j<=n;j++)
						{
							if(adj[j].contains(index) && map.containsKey(j))
								map.put(j, map.get(j)-v[index]);
						}
						map.remove(index);
					}
					pw.println(ans);
					pw.flush();
					pw.close();
					}
				
				public static long fun(long n, long p)
				{
					long[][] f = {{3, 0, 0}, {6, -1, 2}, {0, 0, 1}};
					long[][] t = {{1}, {1}, {1}};
					
					f = matrixpower(f, (n-1)/2, p);
					t = matrixmultiply(f, t, p);
					
					if(n%2 == 0)
						return t[1][0]%p;
					return t[0][0]%p;
				}
				
				public static long[][] matrixpower(long[][] mat, long n, long p)
				{
					int r = mat.length;
					long[][] ans = new long[r][r];
					
					for(int i=0;i<r;i++)
						ans[i][i] = 1;
					
					while(n > 0)
					{
						if(n%2 == 1)
							ans = matrixmultiply(ans, mat, p);
						mat = matrixmultiply(mat, mat, p);
						n /= 2;
					}
					
					return ans;
				}
				
				public static long[][] matrixmultiply(long[][] M1, long[][] M2, long p)
				{
					int m1 = M1.length, m2 = M2[0].length;
					long[][] ans = new long[m1][m2];
					
					for(int i=0;i<m1;i++)
					{
						for(int j=0;j<m2;j++)
						{
							for(int k=0;k<M2.length;k++)
								ans[i][j] = (ans[i][j]%(p) + ((M1[i][k]%(p))*(M2[k][j]%(p)))%(p))%(p);
						}
						//System.out.println(Arrays.toString(ans[i]));
					}
					return ans;
				}
				
				public static long prime(long nth) {
				    
				    long num, count, i;
				    num=1;
				    count=0;
				 
				    while (count < nth){
				      num=num+1;
				      for (i = 2; i <= num; i++){ //Here we will loop from 2 to num
				        if (num % i == 0) {
				          break;
				        }
				      }
				      if ( i == num){//if it is a prime number
				        count = count+1;
				      }
				    }
				    return num;
				  }
			  
				
				public static int[] suffle(int[] a,Random gen)
				{
					int n = a.length;
					for(int i=0;i<n;i++)
					{
						int ind = gen.nextInt(n-i)+i;
						int temp = a[ind];
						a[ind] = a[i];
						a[i] = temp;
					}
					return a;
				}
				
				public static long modularExponentiation(long x,long n,long M)
				{
				    long result=1;
				    while(n>0)
				    {
				        if(n % 2 ==1)
				            result=(result * x)%M;
				        x=(x*x)%M;
				        n=n/2;
				    }
				    return result;
				}
				
				public static long modInverse(long A,long M)
				{
				    return modularExponentiation(A,M-2,M);
				}
				
				public static int BinarySearch_l(long[] a, long k)
				{
					int n = a.length;
					int i = 0, j = n-1;
					int mid = 0;
					
					if(k - a[n-1] > 0)
						return n;
					else
					{
						while(j - i > 0)
						{
							mid = (i+j)/2;
							
							if(k - a[mid] > 0)
								i = mid + 1;
							else
								j = mid;
						}
					}
					
					return i;
				}
				
				public static int BinarySearch_r(long[] a, long k)
				{
					int n = a.length;
					int i = 0, j = n-1;
					int mid = 0;
					
					if(k - a[0] < 0)
						return -1;
					else
					{
						while(j - i > 0)
						{
							mid = (int)Math.ceil((double)(i+j)/2);
							
							if(k - a[mid] >= 0)
								i = mid;
							else
								j = mid - 1;
						}
					}
					
					return i;
				}
				public static long fact(long n, long M)
				{
					long ans = 1;
					
					for(long i=n;i>0;i--)
					{
						ans = (ans*i)%M;
					}
					
					return ans;
				}
				
			/*	public static void DFS(int sourse)
				{
					int count = 0;
					visited[sourse] = true;
					
					for(int u : adj[sourse])
					{
						if(!visited[u])
						{
							DFS(u);
						}
					}
					
					
				}*/
				
				public static ArrayList Divisors(int n)
				{
				    ArrayList<Integer> div = new ArrayList<>();
				    
				    for (int i=1; i<=Math.sqrt(n); i++)
				    {
				        if (n%i == 0)
				        {
				        	div.add(i);
				                
				            if(n/i != i)
				            	div.add(n/i);
				        }
				    }
				    return div;
				}
			
				public static long GCD(long a,long b)
				{
					if(b==0)
						return a;
					else
						return GCD(b,a%b);
				}
				
				public static long LCM(long a,long b)
				{
					return (a*b)/GCD(a, b);
				}
				
				static class pair implements Comparable<pair>
				{
					Integer x, y;
					pair(int x,int y)
					{
						this.x=x;
						this.y=y;
					}
					
					public int compareTo(pair o) {
						int result = x.compareTo(o.x);
						if(result==0)
							result = y.compareTo(o.y);
						
						return result;
					}  
					
					public String toString()
					{
						return x+" "+y;
					}
					
					public boolean equals(Object o)
					{
						if (o instanceof pair)
					    {
							pair p = (pair)o;
							return p.x - x == 0 && p.y - y == 0 ;
						}
						return false;
					}
					
					public int hashCode()
					{
						return new Long(x).hashCode()*31 + new Long(y).hashCode();
					}
				}
				
				static class InputReader 
				{
					 
					private final InputStream stream;
					private final byte[] buf = new byte[8192];
					private int curChar, snumChars;
					private SpaceCharFilter filter;
			 
					public InputReader(InputStream stream) 
					{
						this.stream = stream;
					}
			 
					public int snext() 
					{
						if (snumChars == -1)
							throw new InputMismatchException();
						if (curChar >= snumChars) 
						{
							curChar = 0;
							try 
							{
								snumChars = stream.read(buf);
							} 
							catch (IOException e) 
							{
								throw new InputMismatchException();
							}
							if (snumChars <= 0)
								return -1;
						}
						return buf[curChar++];
					}
			 
					public int nextInt() 
				    {
						int c = snext();
						while (isSpaceChar(c)) 
						{
							c = snext();
						}
						int sgn = 1;
						if (c == '-')
					    {
							sgn = -1;
							c = snext();
						}
						int res = 0;
						do 
						{
							if (c < '0' || c > '9')
								throw new InputMismatchException();
							res *= 10;
							res += c - '0';
							c = snext();
						} while (!isSpaceChar(c));
						return res * sgn;
					}
			 
					public long nextLong()
				    {
						int c = snext();
						while (isSpaceChar(c)) 
						{
							c = snext();
						}
						int sgn = 1;
						if (c == '-') 
						{
							sgn = -1;
							c = snext();
						}
						long res = 0;
						do 
						{
							if (c < '0' || c > '9')
								throw new InputMismatchException();
							res *= 10;
							res += c - '0';
							c = snext();
						} while (!isSpaceChar(c));
						return res * sgn;
					}
			 
					public int[] nextIntArray(int n) 
					{
						int a[] = new int[n];
						for (int i = 0; i < n; i++) 
						{
							a[i] = nextInt();
						}
						return a;
					}
			 
					public String readString()
				    {
						int c = snext();
						while (isSpaceChar(c)) 
						{
							c = snext();
						}
						StringBuilder res = new StringBuilder();
						do 
						{
							res.appendCodePoint(c);
							c = snext();
						} while (!isSpaceChar(c));
						return res.toString();
					}
			 
					public String nextLine() 
					{
						int c = snext();
						while (isSpaceChar(c))
							c = snext();
						StringBuilder res = new StringBuilder();
						do 
						{
							res.appendCodePoint(c);
							c = snext();
						} while (!isEndOfLine(c));
						return res.toString();
					}
			 
					public boolean isSpaceChar(int c) 
					{
						if (filter != null)
							return filter.isSpaceChar(c);
						return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
					}
			 
					private boolean isEndOfLine(int c) 
					{
						return c == '\n' || c == '\r' || c == -1;
					}
			 
					public interface SpaceCharFilter
				    {
						public boolean isSpaceChar(int ch);
					}
				}
				
				static class CodeX {
		        public static void sort(long arr[]) {
		            merge_sort(arr, 0, arr.length - 1);
		        }
		
		        private static void merge_sort(long A[], long start, long end) {
		            if (start < end) {
		                long mid = (start + end) / 2;
		                merge_sort(A, start, mid);
		                merge_sort(A, mid + 1, end);
		                merge(A, start, mid, end);
		            }
		
		        }
		
		        private static void merge(long A[], long start,long mid, long end) {
		            long p = start, q = mid + 1;
		            long Arr[] = new long[(int)(end - start + 1)];
		            long k = 0;
		
		            for (int i = (int)start; i <= end; i++) {
		                if (p > mid)
		                    Arr[(int)k++] = A[(int)q++];
		
		                else if (q > end)
		                    Arr[(int)k++] = A[(int)p++];
		
		                else if (A[(int)p] < A[(int)q])
		                    Arr[(int)k++] = A[(int)p++];
		
		                else
		                    Arr[(int)k++] = A[(int)q++];
		            }
		            for (int i = 0; i < k; i++) {
		                A[(int)start++] = Arr[i];
		            }
		
		        }
		
		    }
			}	
			
	
				