#B. ARC106B - Values

    Type: Default 1000ms 256MiB

ARC106B - Values

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Score : 400 points

Problem Statement

Given is a simple undirected graph with N vertices and M edges. The i-th edge connects Vertex ci and Vertex di. Initially, Vertex i has the value ai written on it. You want to change the values on Vertex 1, , Vertex N to b1, , bN, respectively, by doing the operation below zero or more times.

  • Choose an edge, and let Vertex x and Vertex y be the vertices connected by that edge. Choose one of the following and do it:
    • Decrease the value ax by 1, and increase the value ay by 1.
    • Increase the value ax by 1, and decrease the value ay by 1.

Determine whether it is possible to achieve the objective by properly doing the operation.

Constraints

  • 1N2×105
  • 0M2×105
  • 109ai,bi109
  • 1ci,diN
  • The given graph is simple, that is, has no self-loops and no multi-edges.
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
a1  aN
b1  bN
c1 d1

cM dM

Output

Print Yes if it is possible to achieve the objective by properly doing the operation, and No otherwise.


Sample Input 1

3 2
1 2 3
2 2 2
1 2
2 3

Sample Output 1

Yes

You can achieve the objective by, for example, doing the operation as follows:

  • In the first operation, choose the edge connecting Vertex 1 and 2. Then, increase a1 by 1 and decrease a2 by 1.
  • In the second operation, choose the edge connecting Vertex 2 and 3. Then, increase a2 by 1 and decrease a3 by 1.

This sequence of operations makes a1=2, a2=2, and a3=2.


Sample Input 2

1 0
5
5

Sample Output 2

Yes

The objective may be achieved already in the beginning.


Sample Input 3

2 1
1 1
2 1
1 2

Sample Output 3

No

There is no way to do the operation to achieve the objective.


Sample Input 4

17 9
-905371741 -999219903 969314057 -989982132 -87720225 -175700172 -993990465 929461728 895449935 -999016241 782467448 -906404298 578539175 9684413 -619191091 -952046546 125053320
-440503430 -997661446 -912471383 -995879434 932992245 -928388880 -616761933 929461728 210953513 -994677396 648190629 -530944122 578539175 9684413 595786809 -952046546 125053320
2 10
6 12
9 11
11 5
7 6
3 15
3 1
1 9
10 4

Sample Output 4

Yes

ARC106

Not Attended
Status
Done
Rule
IOI
Problem
6
Start at
2023-7-5 8:15
End at
2023-7-5 10:15
Duration
2 hour(s)
Host
Partic.
13