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



Sample input:
4 3
1 2 3 4
1 3
2 3
2 4


Sample output:
2

Submission status: Accepted

Solution code:
def main(sample_file = ''):

    """ convenient functions
    # for i, a in enumerate(iterable)
    # q, mod = divmod(a, b)
    # divmod(x, y) returns the tuple (x//y, x%y)
    # Higher-order function: reduce(operator.mul, xyz_count, 1)
    # manage median(s) using two heapq https://atcoder.jp/contests/abc127/tasks/abc127_f
    """

    """convenient decorator
    # @functools.lru_cache():
    # to facilitate use of recursive function
        # ex:
        # from functools import lru_cache
        # import sys
        # sys.setrecursionlimit(10**9)
        # @lru_cache(maxsize=None)
        # def fib(n):
        #     if n < 2:
        #         return n
        #     return fib(n-1) + fib(n-2)
        # print(fib(1000))
    """
    
    # import numpy as np
    import sys
    sys.setrecursionlimit(10**7)
    from itertools import accumulate, combinations, permutations, product # https://docs.python.org/ja/3/library/itertools.html
    # accumulate() returns iterator! to get list: list(accumulate())
    from math import factorial, ceil, floor, sqrt
    def factorize(n):
        """return the factors of the Arg and count of each factor
        
        Args:
            n (long): number to be resolved into factors
        
        Returns:
            list of tuples: factorize(220) returns [(2, 2), (5, 1), (11, 1)]
        """
        fct = []  # prime factor
        b, e = 2, 0  # base, exponent
        while b * b <= n:
            while n % b == 0:
                n = n // b
                e = e + 1
            if e > 0:
                fct.append((b, e))
            b, e = b + 1, 0
        if n > 1:
            fct.append((n, 1))
        return fct
    def combinations_count(n, r):   
        """Return the number of selecting r pieces of items from n kinds of items.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        # TODO: How should I do when n - r is negative?
        if n < 0 or r < 0:
            raise Exception('combinations_count(n, r) not defined when n or r is negative')
        if n - r < r: r = n - r
        if r < 0: return 0
        if r == 0: return 1
        if r == 1: return n
        numerator = [n - r + k + 1 for k in range(r)]
        denominator = [k + 1 for k in range(r)]
        for p in range(2,r+1):
            pivot = denominator[p - 1]
            if pivot > 1:
                offset = (n - r) % p
                for k in range(p-1,r,p):
                    numerator[k - offset] /= pivot
                    denominator[k] /= pivot
        result = 1
        for k in range(r):
            if numerator[k] > 1:
                result *= int(numerator[k])
        return result
    def combinations_with_replacement_count(n, r):
        """Return the number of selecting r pieces of items from n kinds of items allowing individual elements to be repeated more than once.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        if n < 0 or r < 0:
            raise Exception('combinations_with_replacement_count(n, r) not defined when n or r is negative')
        elif n == 0:
            return 1
        else:
            return combinations_count(n + r - 1, r)
    from bisect import bisect_left, bisect_right
    from collections import deque, Counter, defaultdict # https://docs.python.org/ja/3/library/collections.html#collections.deque
    from heapq import heapify, heappop, heappush, heappushpop, heapreplace,nlargest,nsmallest # https://docs.python.org/ja/3/library/heapq.html
    from copy import deepcopy, copy # https://docs.python.org/ja/3/library/copy.html
    import operator
    from operator import itemgetter #sort 
    # ex1: List.sort(key=itemgetter(1))
    # ex2: sorted(tuples, key=itemgetter(1,2))
    from functools import reduce, lru_cache
    def chmin(x, y):
        """change minimum
        if x > y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current minimum value
            y (long): potential minimum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x > y:
            x = y
            return (x, True)
        else:
            return (x, False)
    def chmax(x, y):
        """change maximum
        if x < y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current maximum value
            y (long): potential maximum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x < y:
            x = y
            return (x, True)
        else:
            return (x, False)

    from fractions import gcd # Deprecated since version 3.5: Use math.gcd() instead.
    def gcds(numbers):
        return reduce(gcd, numbers)
    def lcm(x, y):
        return (x * y) // gcd(x, y)
    def lcms(numbers):
        return reduce(lcm, numbers, 1)
    def make_divisors(n, reversed=False):
        """create list of divisors
        
        Args:
            number (int): number from which list of divisors is created
            reversed (bool, optional): ascending order if False. Defaults to False.
        
        Returns:
            list: list of divisors
        """
        divisors = set()
        for i in range(1, int(n**0.5)+1):
            if n % i == 0:
                divisors.add(i)
                divisors.add(n//i)
        return sorted(list(divisors),reverse=reversed)
    
    # first create factorial_list
    # fac_list = mod_factorial_list(n)
    INF = 10 ** 18
    MOD = 10 ** 9 + 7
    AtoZ = list('abcdefghijklmnopqrsruvwxyz')
    modpow = lambda a, n, p = MOD: pow(a, n, p) # Recursive function in python is slow!
    def modinv(a, p = MOD):
        # evaluate reciprocal using Fermat's little theorem:
        # a**(p-1) is identical to 1 (mod p) when a and p is coprime
        return modpow(a, p-2, p)
    def modinv_list(n, p = MOD):
        if n <= 1:
            return [0,1][:n+1]
        else:
            inv_t = [0,1]
            for i in range(2, n+1):
                inv_t += [inv_t[p % i] * (p - int(p / i)) % p]
            return inv_t
    def modfactorial_list(n, p = MOD):
        if n == 0:
            return [1]
        else:
            l = [0] * (n+1)
            tmp = 1
            for i in range(1, n+1):
                tmp = tmp * i % p
                l[i] = tmp
            return l
    def modcomb(n, k, fac_list = [], p = MOD):
        # fac_list = modfactorial_list(100)
        # print(modcomb(100, 5, modfactorial_list(100)))
        from math import factorial
        if n < 0 or k < 0 or n < k: return 0
        if n == 0 or k == 0: return 1
        if len(fac_list) <= n:
            a = factorial(n) % p
            b = factorial(k) % p
            c = factorial(n-k) % p
        else:
            a = fac_list[n]
            b = fac_list[k]
            c = fac_list[n-k]
        return (a * modpow(b, p-2, p) * modpow(c, p-2, p)) % p
    def modadd(a, b, p = MOD):
        return (a + b) % MOD
    def modsub(a, b, p = MOD):
        return (a - b) % p
    def modmul(a, b, p = MOD):
        return ((a % p) * (b % p)) % p
    def moddiv(a, b, p = MOD):
        return modmul(a, modpow(b, p-2, p))

    class UnionFindTree:
        """union find tree class
        TODO: fix this description...
        how to use (example):
        >>  uf = UnionFindTree(N) 
        >>  if uf.find_root(a) == uf.find_root(b):
        >>      do something
        >>  else:
        >>      do something
        >>      uf.unite(a, b)
        """
        def __init__(self, N):
            self.root = [-1] * (N+1)
            self.rank   = [0]  * (N+1)
            self.connected_num = [1] * (N+1)
    
        def find_root(self,x):
            root = self.root
            while root[x] != -1:
                x = root[x]
            return x
    
        def unite(self,x,y):
            root = self.root
            rank = self.rank
            connected_num = self.connected_num
            find_root = self.find_root
    
            rx = find_root(x)
            ry = find_root(y)
            if rx != ry:
                if rank[rx] < rank[ry]:
                    root[rx] = ry
                    rx,ry = ry,rx
                else:
                    if rank[rx] == rank[ry]:
                        rank[rx] += 1
                    root[ry] = rx       
                connected_num[rx] += connected_num[ry]

    # Graph: https://en.wikipedia.org/wiki/Directed_graph
    # Bellman-Ford: O(|V||E|). Use this if there exists an edge with negative length in the graph
    # After N steps, the shortest path has converded if there doesn't exist an cycle of edges with negative
    # Watch out: d[N] == d[2*N] doesn't necessarily mean the graph doesn't have negative cycle
    # ref: https://www.youtube.com/watch?v=1Z6ofKN03_Y

    def BellmanFord(N, M, ABC, vertex_start, vertex_end, value_if_inf = -1, find_shortest = False):
        """to calculate furthest or shortest length between vertex_start and vertex_end using BellmanFord algorithm
        
        Args:
            N (int): number of vertices
            M (int): number of edges
            ABC (list): [(ai, bi, ci) for _ in range(N)] where i-th edge is directed from vertex ai to vertex bi and the length is ci 
            vertex_start (int): start vertex. usually use 0.
            vertex_end (int): end vertex. usually use N-1.
            value_if_inf (int or string as you like, optional): value you want when the furthest (or shortest) distance is infinite (or -infinite). Defaults to -1.
            find_shortest (bool, optional): choose False to find furthest path. Defaults to False.
        
        Returns:
            int or string: normally int (but can be str if you set value_if_inf to str)
            
        Example:
                N, M, P = R()
                ABC = [R() for _ in range(M)]
                ABC = [(a-1, b-1, c-P) for a, b, c in ABC]
                print(BellmanFord(N, M, ABC, 0, N-1, value_if_inf = 'inf'))

        """

        def make_reachable_list(N, M, ABC, vertex_start, vertex_end):
            reachable_to_direct = defaultdict(list)
            reachable_from_direct = defaultdict(list)
            reachable_from_start = [False] * N
            reachable_to_end = [False] * N
            reachable_from_start[vertex_start] = True
            reachable_to_end[vertex_end] = True
            reachable_from_both_sides = [False] * N
            dfs_from_start = []
            dfs_to_end = []
            for a, b, c in ABC:
                reachable_to_direct[a].append(b)
                reachable_from_direct[b].append(a)
                if a == vertex_start:
                    dfs_from_start.append(b)
                    reachable_from_start[b] = True
                if b == vertex_end:
                    dfs_to_end.append(a)
                    reachable_to_end[a] = True
            while dfs_from_start:
                v = dfs_from_start.pop()
                for i in reachable_to_direct[v]:
                    if not reachable_from_start[i]:
                        reachable_from_start[i] = True
                        dfs_from_start.append(i)
            while dfs_to_end:
                v = dfs_to_end.pop()
                for i in reachable_from_direct[v]:
                    if not reachable_to_end[i]:
                        reachable_to_end[i] = True
                        dfs_to_end.append(i)
            for i in range(N):
                reachable_from_both_sides[i] = reachable_from_start[i] and reachable_to_end[i]
            return reachable_from_both_sides
        
        reachable_from_both_sides = make_reachable_list(N, M, ABC, vertex_start, vertex_end)
        
        if find_shortest:
            dist = [INF for i in range(N)]
        else:
            dist = [-INF for i in range(N)]
        
        dist[vertex_start] = 0
        for i in range(N):
            updated = False
            for a, b, c in ABC:
                if not reachable_from_both_sides[a]:
                    continue
                elif find_shortest:
                    update_condition = dist[a] + c < dist[b]
                else:
                    update_condition = dist[a] + c > dist[b]
                if dist[a] != INF and update_condition:
                    dist[b] = dist[a] + c
                    updated = True
                    if i == N-1:
                        return value_if_inf
            if not updated:
                break
        return dist[vertex_end]

    """ initialize variables and set inputs
    # initialize variables
        # to initialize list, use [0] * n
        # to initialize two dimentional array:
            # ex) [[0] * N for _ in range(N)]
            # ex2) dp = [[0] * (N+1) for _ in range(W*2)]
    # set inputs
        # put inputs between specific values (almost as quickly)
        # ex) S = [-INF] + [int(r()) for _ in range(A)] + [INF]
        # open(0).read() is sometimes useful:
        # ex) n, m, *x = map(int, open(0).read().split())
        #     min(x[::2]) - max(x[1::2])
        # ex2) *x, = map(int, open(0).read().split())
        #     don't forget to add comma after *x if only one variable is used
    # preprocessing
        # transpose = [x for x in zip(*data)]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [(1, 4, 7), (2, 5, 8), (3, 6, 9)]
        # flat = [flatten for inner in data for flatten in inner]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [1, 2, 3, 4, 5, 6, 7, 8, 9]
    # calculate and output
        # output pattern
        # ex1) print(*l) => when l = [2, 5, 6], printed 2 5 6
    """

    # functions to read input
    r = lambda: sys.stdin.readline().strip()
    r_int = lambda: int(r())
    r_float = lambda: float(r())
    R = lambda: list(map(int, r().split()))
    R_str = lambda: r().split()
    R_map = lambda: map(int, r().split())
    R_float = lambda: list(map(float, r().split()))
    R_tuple = lambda: tuple(map(int, r().split()))

    """ how to treat input
    # single int: int(r())
    # single string: r()
    # single float: float(r())
    # line int: R()
    # line string: r().split()
    # line (str, int, int): [j if i == 0 else int(j) for i, j in enumerate(r().split())]
    # lines int: [R() for _ in range(n)]
    """

    # for test
    if sample_file:
        sys.stdin = open(sample_file)
        
    # ----------------------------------
    # main
    #%%
    N, M = R()
    H = R()
    l = [0] * N
    for m in range(M):
        a, b = R()
        if H[a-1] >= H[b-1]:
            l[b-1] += 1
        if H[b-1] >= H[a-1]:
            l[a-1] += 1
    ans = 0
    for ll in l:
        if ll == 0:
            ans += 1
    print(ans)


    #%%
    # end of main
    # ----------------------------------

    """memo: how to use defaultdict of list
    # initialize
    Dic = defaultdict(list)
    # append / extend
    Dic[x].append(y)
    # three methods for loop: keys(), values(), items()
    for k, v in Dic.items():
    """
    
    """memo: how to solve binary problems
    # to make binary digits text
    >>> a = 5
    >>> bin_str_a = format(a, '#06b')
    >>> print(bin_str_a)
    0b0101 # first 2 strings (='0b') indicates it is binary
    """
    
    """memo: how to solve the problem
    creating simple test/answer
    greed
    simple dp
    graph
    """

if __name__ == '__main__':
    main()

Submission status: Accepted

Solution code:
n, m = map(int, input().split())
h = list(map(int, input().split()))
g = [1]*n
for i in range(m):
  a, b = map(int, input().split())
  if h[a-1] <= h[b-1]:
    g[a-1] = 0
  if h[a-1] >= h[b-1]:
    g[b-1] = 0
print(g.count(1))

Submission status: Accepted

Solution code:
N, M = map(int, input().split())

highs = list(map(int, input().split()))

loads = [set([]) for _ in range(N)]

for _ in range(M):
    a, b = map(int, input().split())
    loads[a - 1].add(b - 1)
    loads[b - 1].add(a - 1)
# print(highs)
# print(loads)
count = 0
for i, tower_loads in enumerate(loads):
    highest = True
    for load in tower_loads:
        if highs[i] <= highs[load]:
            highest = False
            break
    if highest:
        # print(i)
        count += 1
print(count)

Submission status: Accepted

Solution code:
N,M = map(int,input().split())
H = list(map(int,input().split()))
high = [1] * N

for i in range(M):
  A,B = map(int,input().split())
  if H[A-1] < H[B-1]:
    high[A-1] = 0
  elif H[A-1] > H[B-1]:
    high[B-1] = 0
  else:
    high[A-1] = 0
    high[B-1] = 0

print(sum(high))

Submission status: Accepted

Solution code:
N, M = map(int, input().split())
H = list(map(int, input().split()))
li = []
count = 0
for i in H:
    li.append([i])
for i in range(M):
    s1, s2 = map(int, input().split())
    li[s1-1].append(s2)
    li[s2-1].append(s1)
for i in range(len(li)):
    flag = 1
    for j in range(1, len(li[i])):
        if li[i][0] <= H[li[i][j]-1]:
            flag = 0
    if flag == 1:
        count += 1
print(count)

Submission status: Accepted

Solution code:
N, M = map(int, input().split())
H = list(map(int, input().split()))

h = []
for i in H:
    h.append(i)
for i in range(M):
    a, b = map(int, input().split())
    if h[a-1] <= H[b-1] and h[a-1] != -1:
        h[a-1] = -1
    if h[b-1] <= H[a-1] and h[b-1] != -1:
        h[b-1] = -1

ans = N
for i in h:
    if i == -1:
        ans -= 1

print(ans)

Submission status: Accepted

Solution code:
N, M = map(int, input().split())

H = list(map(int, input().split()))

road = [[] for _ in range(N)]

for _ in range(M):
    a, b = map(int, input().split())
    road[a-1].append(H[b-1])
    road[b-1].append(H[a-1])

ans = 0
for i in range(N):
    if not road[i]:
        ans += 1
    elif H[i] > max(road[i]):
        ans += 1

print(ans)

Submission status: Accepted

Solution code:
def resolve():
    N, M = map(int, input().split())
    H = list(map(int, input().split()))
    g = [1] * N
    for _ in range(M):
        a, b = map(int, input().split())
        a -= 1
        b -= 1
        if H[a] <= H[b]:
            g[a] = 0
        if H[b] <= H[a]:
            g[b] = 0

    print(sum(g))
resolve()

Submission status: Accepted

Solution code:
N,M = map(int,input().split())
H = list(map(int,input().split()))
lose = []
for i in range(M):
    A,B = map(int,input().split())
    if(H[A-1]>H[B-1]):
        loser = B
    elif(H[B-1]>H[A-1]):
        loser= A
    else:
        lose.append(A)
        lose.append(B)
        continue
    lose.append(loser)
set_lose = set(lose)
print(N-len(set_lose))

Submission status: Accepted

Solution code:
#!/bin/bash
''':'
docker run --rm -it -v $(cd $(dirname $0) && pwd):/vo:ro pypy:3-2.4.0 \
   /bin/bash -c "pypy3 /vo/$(basename $0) < /vo/input.txt"
exit $?
'''
import sys


def _i(): return int(sys.stdin.readline().strip())


def _ia(): return map(int, sys.stdin.readline().strip().split())


def main():
    n, m = _ia()
    h = list(_ia())
    adj = [[] for _ in range(n)]
    for _ in range(m):
        a, b = _ia()
        adj[a-1].append(b-1)
        adj[b-1].append(a-1)
    ans = 0
    for i in range(n):
        hi = h[i]
        f = True
        for j in adj[i]:
            hj = h[j]
            if hi <= hj:
                f = False
                break
        if f:
            ans += 1
    return ans


if __name__ == "__main__":
    print(main())

Submission status: Accepted

Solution code:
N, M = map(int, input().split())
Hs = list(map(int, input().split()))

lis = [[-1] for _ in range(N)]

for _ in range(M):
    A, B = map(int, input().split())
    lis[A-1].append(B-1)
    lis[B-1].append(A-1)

ans = 0
for i in range(N):
    L = lis[i]
    H = Hs[i]
    flg = True
    for j in L:
        if j==-1:
            continue
        if H<=Hs[j]:
            flg = False
            break
    if flg:
        ans += 1
print(ans)

Submission status: Accepted

Solution code:
from collections import defaultdict,deque
import sys, bisect, math, itertools
from functools import lru_cache
# @lru_cache(maxsize=None)
sys.setrecursionlimit(10**8)
input = sys.stdin.readline
INF = float('inf')
mod = 10**9+7
eps = 10**-7
def inp():
    '''
    一つの整数
    '''
    return int(input())
def inpl():
    '''
    一行に複数の整数
    '''
    return list(map(int, input().split()))

n, m = inpl()
h = inpl()
v=[True for i in range(n)]
for i in range(m):
    a, b = inpl()  # h[a-1]>h[b-1]
    if h[a - 1] == h[b - 1]:
        v[a - 1] = False
        v[b - 1] = False
    elif h[a - 1] < h[b - 1]:
        v[a - 1] = False
    else:
        v[b - 1] = False
print(v.count(True))

Submission status: Accepted

Solution code:
N,M = map(int,input().split())
H = list(map(int,input().split()))

tmb=[1]*N#0-N-1
for i in range(0,M,1):
    A,B = map(int,input().split())#indずれ
    if H[A-1]==H[B-1]:
        tmb[A-1]=0
        tmb[B-1]=0
    elif H[A-1]<H[B-1]:
        tmb[A-1]=0
    elif H[B-1]<H[A-1]:
        tmb[B-1]=0

print(sum(tmb))

Submission status: Accepted

Solution code:
n,m=map(int,input().split())
h=list(map(int,input().split()))
ab=[list(map(int,input().split())) for _ in range(m)]
g=[[]for _ in range(n)]
for a,b in ab:
  g[a-1].append(b-1)
  g[b-1].append(a-1)
ans=0
for i in range(n):
  c=h[i]
  t=True
  for j in g[i]:
    if c<=h[j]:
      t=False
      break
  ans+=1 if t else 0
print(ans)

Submission status: Accepted

Solution code:
n,m = map(int, input().split())
h = list(map(int, input().split()))
goods = [1]*n
for _ in range(m):
    a,b = map(int, input().split())
    if h[a-1] > h[b-1]:
        goods[b-1] = 0
    elif h[a-1] < h[b-1]:
        goods[a-1] = 0
    elif h[a-1] == h[b-1]:
        goods[a-1] = 0
        goods[b-1] = 0
print(sum(goods))

Submission status: Accepted

Solution code:
n, m = map(int, input().split())
h = list(map(int, input().split()))
ans = [1] * n

for i in range(m):
    a, b = map(int, input().split())
    if h[a - 1] < h[b - 1]:
        ans[a - 1] = 0
    elif h[a - 1] > h[b - 1]:
        ans[b - 1] = 0
    else:
        ans[a - 1] = 0
        ans[b - 1] = 0
print(ans.count(1))

Submission status: Accepted

Solution code:
inf = 10**15
mod = 10**9+7
n,m = map(int, input().split())
h = list(map(int, input().split()))
judge = [1 for i in range(n)]
for i in range(m):
    a,b = map(int, input().split())
    if h[a-1] > h[b-1]:
        judge[b-1] = 0
    elif h[b-1] > h[a-1]:
        judge[a-1] = 0
    else:
        judge[b - 1] = 0
        judge[a - 1] = 0
print(sum(judge))

Submission status: Accepted

Solution code:
from sys import stdin
input = stdin.readline

n, m = map(int, input().split())
h = [int(x) for x in input().split()]

h.insert(0, 0)

c = [[0] for x in range(n + 1)]

for _ in range(m):
    a, b = map(int, input().split())

    c[a].append(h[b])
    c[b].append(h[a])

cnt = 0

for x in range(1, n + 1):
    if h[x] > max(c[x]):
        cnt += 1

print(cnt)

Submission status: Accepted

Solution code:
from collections import defaultdict

n,m = map(int, input().split())
hs = {i+1: x for i,x in enumerate(map(int, input().split()))}
neighbor = defaultdict(set)
for _ in range(m):
  a,b = map(int, input().split())
  neighbor[a] |= {b}
  neighbor[b] |= {a}

c = 0
check = set()
for k in hs.keys():
  if k in check: continue
  flag = True
  for x in neighbor[k]:
    if hs[x] < hs[k]:
      check |= {x}
    else:
      flag = False
  if flag:
    c += 1
print(c)

Submission status: Accepted

Solution code:
n, m = list(map(int, input().split()))
h = list(map(int, input().split()))
observ = [set() for _ in range(n)]
for i in range(m):
    a, b = list(map(int, input().split()))
    observ[a-1].add(b-1)
    observ[b-1].add(a-1)

cnt = 0
for i, o in enumerate(observ):
    height = h[i]
    flg = True
    for oh in o:
        if height <= h[oh]:
            flg = False
            break
    if flg:
        cnt += 1

print(cnt)

Submission status: Accepted

Solution code:
N, M = [int(i) for i in input().split(" ")]
H = [int(i) for i in input().split(" ")]

node = [[] for _ in range(N)]

for i in range(M):
    a,b = [int(i) for i in input().split(" ")]
    node[a-1].append(b-1)
    node[b-1].append(a-1)

ans = 0
for n,i in enumerate(node):
    i_high = H[n]
    for j in i:
        if H[j] >= i_high:
            break
    else:
        ans += 1

print(ans)

Submission status: Accepted

Solution code:
import collections
N, M = [int(_) for _ in input().split()]
H = [int(_) for _ in input().split()]
I = [i for v, i in sorted([(v, i) for i, v in enumerate(H)], reverse=True)]
G = collections.defaultdict(set)
for _ in range(M):
    a, b = [int(_) for _ in input().split()]
    a -= 1
    b -= 1
    G[a].add(b)
    G[b].add(a)
visited = set()
ans = 0
for i in I:
    visited.add(i)
    f = True
    for j in G[i]:
        visited.add(j)
        if H[j] >= H[i]:
            f = False
    if f:
        ans += 1
print(ans)

Submission status: Accepted

Solution code:
n,m = map(int,input().split())
H = list(map(int,input().split()))
G = [[] for _ in range(n)]
for i in range(m):
  a,b = map(int,input().split())
  G[a-1].append(H[b-1])
  G[b-1].append(H[a-1])

ans = 0  
for i in range(n):
  if len(G[i])==0:
    ans += 1
  else:
    if H[i] > max(G[i]):
      ans += 1

print(ans)

Submission status: Accepted

Solution code:
N, M = map(int, input().split())
H = list(map(int, input().split()))
AB = [list(map(int, input().split())) for _ in range(M)]
result = 0
flag = [True] * N
result = N
for a, b in AB:
    if H[a-1] < H[b-1]:
        flag[a-1] = False
    elif H[a-1] > H[b-1]:
        flag[b-1] = False
    else:
        flag[a-1] = False
        flag[b-1] = False
print(flag.count(True))

Submission status: Accepted

Solution code:
# -*- coding: utf-8 -*-

def input_one_number():
    return int(input())

def input_multiple_number():
    return map(int, input().split())

def input_multiple_number_as_list():
    return list(map(int, input().split()))


N,M =  input_multiple_number()

listH  = input_multiple_number_as_list()

isGood = [True]*N
for i in range(M):
	A,B = input_multiple_number()

	if listH[A-1] > listH[B-1]:
		isGood[B-1] = False
	elif listH[A-1] < listH[B-1]:
		isGood[A-1] = False
	else:
		isGood[B-1] = False
		isGood[A-1] = False

cnt = 0
for i in isGood:
	if i == True:
		cnt += 1

										
print(cnt)

Submission status: Accepted

Solution code:
import sys
def input():
    return sys.stdin.readline().rstrip('\n')


def calc(N, M, H, C):
    f = [1 for _ in range(N)]
    for a, b in C:
        if H[a] == H[b]:
            f[a] = f[b] = 0
        elif H[a] > H[b]:
            f[b] = 0
        else:
            f[a] = 0
    return sum(f)
    

(N, M) = tuple([int(s) for s in input().split()])
H = [int(s) for s in input().split()]
C = [tuple([int(s) - 1 for s in input().split()]) for _ in range(M)]
print(calc(N, M, H, C))

Submission status: Accepted

Solution code:
import sys
readline = sys.stdin.buffer.readline
sys.setrecursionlimit(10 ** 8)
INF = float('inf')
MOD = 10 ** 9 + 7

def main():
    N, M = map(int, input().split())
    H = list(map(int, input().split()))
    good = [True]*N
    for _ in range(M):
        a, b = map(int, input().split())
        if H[a-1]==H[b-1]:
            good[a-1]=False
            good[b-1]=False
        elif H[a-1]<H[b-1]:
            good[a-1] = False
        else:
            good[b-1]=False
    print(sum(good))


if __name__ == '__main__':
    main()

Submission status: Accepted

Solution code:
def main():
    n, m = map(int, input().split())
    h = list(map(int, input().split()))
    G = [[] for _ in range(n)]
    for _ in range(m):
        a, b = map(int, input().split())
        a, b = a-1, b-1
        G[a].append(b)
        G[b].append(a)
    f = [True]*n
    for i in range(n):
        if not f[i]:
            continue
        x = h[i]
        for v in G[i]:
            if h[i] < h[v]:
                f[i] = False
            elif h[i] == h[v]:
                f[i] = False
                f[v] = False
            else:
                f[v] = False
    ans = 0
    for i in range(n):
        if f[i]:
            ans += 1
    print(ans)

if __name__ == "__main__":
    main()

Submission status: Accepted

Solution code:
n, m = map(int, input().split())
peak = list(map(int, input().split()))
lst = [list(map(int, input().split())) for i in range(m)]

hlst = [[] for i in range(n)]
for i in range(m):
  hlst[lst[i][1]-1].append(peak[lst[i][0]-1])
  hlst[lst[i][0]-1].append(peak[lst[i][1]-1])

ans = 0

for i in range(n):
  judge = True
  for j in range(len(hlst[i])):
    if hlst[i][j] >= peak[i]:
      judge = False
      break
  if judge:
    ans += 1
                 
print(ans)

Submission status: Accepted

Solution code:
N, M = map(int, input().split())
H = list(map(int, input().split()))
W = []

for i in range(M):
  A, B = map(int, input().split())
  if H[A-1] == H[B-1]:
    W.append(A)
    W.append(B)
  elif H[A-1] >= H[B-1]:
    W.append(B)
  else:
    W.append(A)

print( N - len(set(W)) )