LeetCode-in-Java
780. Reaching Points
Hard
Given four integers sx, sy, tx, and ty, return true if it is possible to convert the point (sx, sy) to the point (tx, ty) through some operations__, or false otherwise.
The allowed operation on some point (x, y) is to convert it to either (x, x + y) or (x + y, y).
Example 1:
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)
Example 2:
Input: sx = 1, sy = 1, tx = 2, ty = 2
Output: false
Example 3:
Input: sx = 1, sy = 1, tx = 1, ty = 1
Output: true
Constraints:
1 <= sx, sy, tx, ty <= 109
Solution
public class Solution {
public boolean reachingPoints(int sx, int sy, int tx, int ty) {
while (tx >= sx && ty >= sy) {
if (tx > ty) {
if (ty == sy) {
// ty==sy
return (tx - sx) % sy == 0;
} else {
// ty > sy
tx %= ty;
}
} else if (sx == tx) {
// ty >= tx
return (ty - sy) % sx == 0;
} else {
// (tx > sx)
ty %= tx;
}
}
return false;
}
}