- Reaching Points Hard
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Share A move consists of taking a point (x, y) and transforming it to either (x, x+y) or (x+y, y).
Given a starting point (sx, sy) and a target point (tx, ty), return True if and only if a sequence of moves exists to transform the point (sx, sy) to (tx, ty). Otherwise, return False.
Examples: Input: sx = 1, sy = 1, tx = 3, ty = 5 Output: True Explanation: One series of moves that transforms the starting point to the target is: (1, 1) -> (1, 2) (1, 2) -> (3, 2) (3, 2) -> (3, 5)
Input: sx = 1, sy = 1, tx = 2, ty = 2 Output: False
Input: sx = 1, sy = 1, tx = 1, ty = 1 Output: True
思路：如果tx>ty,说明最后一步是tx=tx+ty,那就tx对ty求余，排除ty，循环 如果tx==sx，说明tx目前的值即为最小值，（ty-tx）%sy == 0，说明可以，否则不可以
代码：python3
class Solution:
def reachingPoints(self, sx, sy, tx, ty) :
x=tx
y=ty
if sx==tx and sy==ty:
return True
while (y>=sy and x>=sx):
if y>x:
y=y%x
else:
x=x%y
if x>y:
return x==sx and y==sy%sx
return y==sy and x==sx%sy
if __name__ == '__main__':
print(Solution().reachingPoints(3,3,12,9))
