https://www.acmicpc.net/problem/1072
import math
X, Y = map(int, input().split())
Z = (Y * 100) // X
if Z >= 99:
print(-1)
else:
right = X
left = 1
answer = 0
while left <= right:
mid = (left + right) // 2
if (Y + mid) * 100 // (X + mid) <= Z:
left = mid+1
else:
answer = mid
right = mid - 1
print(answer)