[25304] 영수증

total = int(input())
count = int(input())
lists = []
sums = 0
for i in range(count):
    lists.append(list(map(int, input().split())))

for i in range(count):
    sums = sums + lists[i][0] * lists[i][1]

if sums == total :
    print("Yes")
else:
    print("No")