有两个水壶,容量分别为 jug1Capacity 和 jug2Capacity 升。水的供应是无穷的。确定是否有大概使用这两个壶精确得到 targetCapacity 升。
假如可以得到 targetCapacity 升水,末了请用以上水壶中的一或两个来盛放取得的 targetCapacity 升水。
你可以:
装满恣意一个水壶
清空恣意一个水壶
从一个水壶向别的一个水壶倒水,直到装满大概倒空
示例 1:
输入: jug1Capacity = 3, jug2Capacity = 5, targetCapacity = 4
输出: true
表明:来自闻名的 "Die Hard"
示例 2:
输入: jug1Capacity = 2, jug2Capacity = 6, targetCapacity = 5
输出: false
示例 3:
输入: jug1Capacity = 1, jug2Capacity = 2, targetCapacity = 3
输出: true
java代码:
class Solution { public boolean canMeasureWater(int x, int y, int z) { Deque<int[]> stack = new LinkedList<int[]>(); stack.push(new int[]{0, 0}); Set<Long> seen = new HashSet<Long>(); while (!stack.isEmpty()) { if (seen.contains(hash(stack.peek()))) { stack.pop(); continue; } seen.add(hash(stack.peek())); int[] state = stack.pop(); int remain_x = state[0], remain_y = state[1]; if (remain_x == z || remain_y == z || remain_x + remain_y == z) { return true; } // 把 X 壶灌满。 stack.push(new int[]{x, remain_y}); // 把 Y 壶灌满。 stack.push(new int[]{remain_x, y}); // 把 X 壶倒空。 stack.push(new int[]{0, remain_y}); // 把 Y 壶倒空。 stack.push(new int[]{remain_x, 0}); // 把 X 壶的水灌进 Y 壶,直至灌满或倒空。 stack.push(new int[]{remain_x - Math.min(remain_x, y - remain_y), remain_y + Math.min(remain_x, y - remain_y)}); // 把 Y 壶的水灌进 X 壶,直至灌满或倒空。 stack.push(new int[]{remain_x + Math.min(remain_y, x - remain_x), remain_y - Math.min(remain_y, x - remain_x)}); } return false; } public long hash(int[] state) { return (long) state[0] * 1000001 + state[1]; }} |