Problem:
Score : 300 points

Problem Statement

There are N observatories in AtCoder Hill, called Obs. 1, Obs. 2, ..., Obs. N. The elevation of Obs. i is H_i.
There are also M roads, each connecting two different observatories. Road j connects Obs. A_j and Obs. B_j.

Obs. i is said to be good when its elevation is higher than those of all observatories that can be reached from Obs. i using just one road.
Note that Obs. i is also good when no observatory can be reached from Obs. i using just one road.

How many good observatories are there?

Constraints

2 \leq N \leq 10^5

1 \leq M \leq 10^5

1 \leq H_i \leq 10^9

1 \leq A_i,B_i \leq N

A_i \neq B_i

Multiple roads may connect the same pair of observatories.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
H_1 H_2 ... H_N
A_1 B_1
A_2 B_2
:
A_M B_M

Output

Print the number of good observatories.

Sample Input 1

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

Sample Output 1

2

From Obs. 1, you can reach Obs. 3 using just one road. The elevation of Obs. 1 is not higher than that of Obs. 3, so Obs. 1 is not good.

From Obs. 2, you can reach Obs. 3 and 4 using just one road. The elevation of Obs. 2 is not higher than that of Obs. 3, so Obs. 2 is not good.

From Obs. 3, you can reach Obs. 1 and 2 using just one road. The elevation of Obs. 3 is higher than those of Obs. 1 and 2, so Obs. 3 is good.

From Obs. 4, you can reach Obs. 2 using just one road. The elevation of Obs. 4 is higher than that of Obs. 2, so Obs. 4 is good.

Thus, the good observatories are Obs. 3 and 4, so there are two good observatories.

Sample Input 2

6 5
8 6 9 1 2 1
1 3
4 2
4 3
4 6
4 6

Sample Output 2

3

Solution in PyPy3 (7.3.0) (judge verdict: Wrong Answer)

"""
~~ author : dokueki
~~ created : 10~05~2020
"""

import sys
INT_MAX = sys.maxsize
INT_MIN = -(sys.maxsize)-1
sys.setrecursionlimit(10**7)
mod = 1000000007


def IOE():
    sys.stdin = open("input.txt", "r")
    sys.stdout = open("output.txt", "w")


def main():
    n, m = map(int, sys.stdin.readline().split())
    h = list(map(int, sys.stdin.readline().split()))
    set_h = set()
    links = dict()
    for i in range(1, n + 1):
        links[h[i-1]] = set()
    v = set()
    for i in range(m):
        a, b = map(int, sys.stdin.readline().split())
        links[h[a-1]].add(h[b-1])
        links[h[b-1]].add(h[a - 1])
    cnt = 0
    c = 0
    # visited = set()
    for k, v in links.items():
        if len(v):
            for j in v:
                if k > j:
                    c += 1
            if c == len(v):
                cnt += 1
        else:
            cnt += 1
    # print(links)
    print(cnt)


if __name__ == "__main__":
    try:
        IOE()
    except:
        pass
    main()