Buggy python submission (verdict: Runtime Error):
import sys, re, os
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from heapq import heapify, heappop, heappush
from bisect import bisect_right

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def S_MAP(): return map(str, input().split())
def LIST(): return list(map(int, input().split()))
def S_LIST(): return list(map(str, input().split()))
 
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]
dic = defaultdict(int)

# for a, b in L:
    # dic[A[a]] = b
A.sort()
L = sorted(L, key=lambda x : x[1], reverse=True)
# print(L)
i = 0
# for i, a in enumerate(A):
for f, t in L:
    while f > 0:
        if t > A[i]:
            A[i] = t
            f -= 1
            i += 1
        else:
            print(sum(A))
            exit()
print(sum(A))
    
    

Fixed submission:
import sys, re, os
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from fractions import gcd
import heapq

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def S_MAP(): return map(str, input().split())
def LIST(): return list(map(int, input().split()))
def S_LIST(): return list(map(str, input().split()))

sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]
L = sorted(L, key=lambda x : x[1], reverse=True)
default_sum = sum(A)

heapq.heapify(A)  # リストを優先度付きキューへ

for max_cnt, target in L:
    cnt = 0
    while cnt < max_cnt and len(A) != 0:
        min_num = heapq.heappop(A) # pop min
        default_sum += max(target - min_num, 0)
        cnt += 1
    
print(default_sum)



    

exit()
print(heapq.heappop(a))  # 最小値の取り出し

heapq.heappush(a, -2)  # 要素の挿入
print(a)
for i in range(M):
    a = heapq.heappop(A) * (-1)
    a = a // 2
    heapq.heappush(A, -a)
A = list(map(lambda x: x * (-1), A))
print(sum(A))

Buggy python submission (verdict: Runtime Error):
import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import accumulate, permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left
from fractions import gcd
from heapq import heappush, heappop
from functools import reduce
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]

L = sorted(L, key=lambda x: x[1], reverse=True) # 0番目の要素でソート

A.sort()
n = 0
for i in range(M):
    times, num = L[i]
    while times > 0 or n == N:
        if A[n] < num:
            A[n] = num
            times -= 1
            n += 1
        else:
            print(sum(A))
            exit()
print(sum(A))


    



Fixed submission:
import sys, re, os
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from fractions import gcd
import heapq

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def S_MAP(): return map(str, input().split())
def LIST(): return list(map(int, input().split()))
def S_LIST(): return list(map(str, input().split()))

sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]
L = sorted(L, key=lambda x : x[1], reverse=True)
default_sum = sum(A)

heapq.heapify(A)  # リストを優先度付きキューへ

for max_cnt, target in L:
    cnt = 0
    while cnt < max_cnt and len(A) != 0:
        min_num = heapq.heappop(A) # pop min
        default_sum += max(target - min_num, 0)
        cnt += 1
    
print(default_sum)



    

exit()
print(heapq.heappop(a))  # 最小値の取り出し

heapq.heappush(a, -2)  # 要素の挿入
print(a)
for i in range(M):
    a = heapq.heappop(A) * (-1)
    a = a // 2
    heapq.heappush(A, -a)
A = list(map(lambda x: x * (-1), A))
print(sum(A))

Buggy python submission (verdict: Runtime Error):
import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import accumulate, permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left
from fractions import gcd
from heapq import heappush, heappop
from functools import reduce
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]

L = sorted(L, key=lambda x: x[1], reverse=True) # 0番目の要素でソート

A.sort()
n = 0
for i in range(M):
    times, num = L[i]
    while times > 0:
        if A[n] < num:
            A[n] = num
            times -= 1
            n += 1
        else:
            print(sum(A))
            exit()
print(sum(A))


    



Fixed submission:
import sys, re, os
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from fractions import gcd
import heapq

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def S_MAP(): return map(str, input().split())
def LIST(): return list(map(int, input().split()))
def S_LIST(): return list(map(str, input().split()))

sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]
L = sorted(L, key=lambda x : x[1], reverse=True)
default_sum = sum(A)

heapq.heapify(A)  # リストを優先度付きキューへ

for max_cnt, target in L:
    cnt = 0
    while cnt < max_cnt and len(A) != 0:
        min_num = heapq.heappop(A) # pop min
        default_sum += max(target - min_num, 0)
        cnt += 1
    
print(default_sum)



    

exit()
print(heapq.heappop(a))  # 最小値の取り出し

heapq.heappush(a, -2)  # 要素の挿入
print(a)
for i in range(M):
    a = heapq.heappop(A) * (-1)
    a = a // 2
    heapq.heappush(A, -a)
A = list(map(lambda x: x * (-1), A))
print(sum(A))

Buggy python submission (verdict: Time Limit Exceeded):
N, M = map(int, input().split())
A = list(map(int, input().split()))
A.sort()
for i in range(M):
    b, c = map(int, input().split())
    for i in range(N):
        if b > 0:
            if A[i] < c:
                A[i] = c
                b -= 1
    A.sort()

print(sum(A))
     






Fixed submission:
import sys, re, os
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from fractions import gcd
import heapq

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def S_MAP(): return map(str, input().split())
def LIST(): return list(map(int, input().split()))
def S_LIST(): return list(map(str, input().split()))

sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N, M = MAP()
A = LIST()
L = [LIST() for i in range(M)]
L = sorted(L, key=lambda x : x[1], reverse=True)
default_sum = sum(A)

heapq.heapify(A)  # リストを優先度付きキューへ

for max_cnt, target in L:
    cnt = 0
    while cnt < max_cnt and len(A) != 0:
        min_num = heapq.heappop(A) # pop min
        default_sum += max(target - min_num, 0)
        cnt += 1
    
print(default_sum)



    

exit()
print(heapq.heappop(a))  # 最小値の取り出し

heapq.heappush(a, -2)  # 要素の挿入
print(a)
for i in range(M):
    a = heapq.heappop(A) * (-1)
    a = a // 2
    heapq.heappush(A, -a)
A = list(map(lambda x: x * (-1), A))
print(sum(A))