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feat: add solutions to lc problem: No.1046
No.1046.Last Stone Weight
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‎solution/1000-1099/1046.Last Stone Weight/README.md

Lines changed: 46 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -43,6 +43,14 @@
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<!-- 这里可写通用的实现逻辑 -->
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**方法一：大根堆（优先队列）**
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将 `stones` 数组所有元素放入大根堆，执行循环操作，每次弹出两个元素 `x` 和 `y`，如果 `x != y`，将 `x - y` 放入大根堆。当堆元素个数小于 `2` 时，退出循环。
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最后如果存在堆顶元素，则将其返回，否则返回 `0`。
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时间复杂度 $O(n\log n)$，空间复杂度 $O(n)$。其中 $n$ 是 `stones` 数组的长度。
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<!-- tabs:start -->
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### **Python3**
@@ -52,13 +60,14 @@
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```python
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class Solution:
5462
def lastStoneWeight(self, stones: List[int]) -> int:
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h = [-s for s in stones]
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h = [-v for v in stones]
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heapify(h)
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while len(h) > 1:
58-
y, x = -heappop(h), -heappop(h)
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x = heappop(h)
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y = heappop(h)
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if x != y:
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heappush(h, x - y)
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return 0 if not h else -h[0]
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return 0 if len(h) == 0 else -h[0]
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```
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### **Java**
@@ -68,18 +77,18 @@ class Solution:
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```java
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class Solution {
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public int lastStoneWeight(int[] stones) {
71-
Queue<Integer> queue = new PriorityQueue<>(Comparator.reverseOrder());
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for (int stone : stones) {
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queue.offer(stone);
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PriorityQueue<Integer> q = new PriorityQueue<>((a, b) -> b - a);
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for (int v : stones) {
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q.offer(v);
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}
75-
while (queue.size() > 1) {
76-
int x = queue.poll();
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int y = queue.poll();
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while (q.size() > 1) {
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int y = q.poll();
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int x = q.poll();
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if (x != y) {
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queue.offer(x - y);
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q.offer(y - x);
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}
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}
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return queue.isEmpty() ? 0 : queue.poll();
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return q.isEmpty() ? 0 : q.poll();
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}
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}
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```
@@ -92,12 +101,9 @@ public:
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int lastStoneWeight(vector<int>& stones) {
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priority_queue<int> pq(stones.begin(), stones.end());
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while (pq.size() > 1) {
95-
int x = pq.top();
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pq.pop();
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int y = pq.top();
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pq.pop();
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if (x != y)
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pq.push(x - y);
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int x = pq.top(); pq.pop();
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int y = pq.top(); pq.pop();
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if (x != y) pq.push(x - y);
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}
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return pq.empty() ? 0 : pq.top();
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}
@@ -136,6 +142,29 @@ func (h *hp) push(v int) { heap.Push(h, v) }
136142
func (h *hp) pop() int { return heap.Pop(h).(int) }
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```
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### **JavaScript**
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```js
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/**
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* @param {number[]} stones
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* @return {number}
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*/
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var lastStoneWeight = function (stones) {
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const pq = new MaxPriorityQueue();
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for (const v of stones) {
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pq.enqueue(v);
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}
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while (pq.size() > 1) {
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const x = pq.dequeue()['priority'];
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const y = pq.dequeue()['priority'];
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if (x != y) {
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pq.enqueue(x - y);
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}
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}
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return pq.isEmpty() ? 0 : pq.dequeue()['priority'];
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};
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```
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### **...**
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```

‎solution/1000-1099/1046.Last Stone Weight/README_EN.md

Lines changed: 38 additions & 17 deletions
Original file line numberDiff line numberDiff line change
@@ -54,32 +54,33 @@ we combine 1 and 1 to get 0 so the array converts to [1] then that&#39;s the val
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```python
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class Solution:
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def lastStoneWeight(self, stones: List[int]) -> int:
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h = [-s for s in stones]
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h = [-v for v in stones]
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heapify(h)
5959
while len(h) > 1:
60-
y, x = -heappop(h), -heappop(h)
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x = heappop(h)
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y = heappop(h)
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if x != y:
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heappush(h, x - y)
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return 0 if not h else -h[0]
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return 0 if len(h) == 0 else -h[0]
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```
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### **Java**
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```java
6970
class Solution {
7071
public int lastStoneWeight(int[] stones) {
71-
Queue<Integer> queue = new PriorityQueue<>(Comparator.reverseOrder());
72-
for (int stone : stones) {
73-
queue.offer(stone);
72+
PriorityQueue<Integer> q = new PriorityQueue<>((a, b) -> b - a);
73+
for (int v : stones) {
74+
q.offer(v);
7475
}
75-
while (queue.size() > 1) {
76-
int x = queue.poll();
77-
int y = queue.poll();
76+
while (q.size() > 1) {
77+
int y = q.poll();
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int x = q.poll();
7879
if (x != y) {
79-
queue.offer(x - y);
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q.offer(y - x);
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}
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}
82-
return queue.isEmpty() ? 0 : queue.poll();
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return q.isEmpty() ? 0 : q.poll();
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}
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}
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```
@@ -92,12 +93,9 @@ public:
9293
int lastStoneWeight(vector<int>& stones) {
9394
priority_queue<int> pq(stones.begin(), stones.end());
9495
while (pq.size() > 1) {
95-
int x = pq.top();
96-
pq.pop();
97-
int y = pq.top();
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pq.pop();
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if (x != y)
100-
pq.push(x - y);
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int x = pq.top(); pq.pop();
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int y = pq.top(); pq.pop();
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if (x != y) pq.push(x - y);
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}
102100
return pq.empty() ? 0 : pq.top();
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}
@@ -136,6 +134,29 @@ func (h *hp) push(v int) { heap.Push(h, v) }
136134
func (h *hp) pop() int { return heap.Pop(h).(int) }
137135
```
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137+
### **JavaScript**
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```js
140+
/**
141+
* @param {number[]} stones
142+
* @return {number}
143+
*/
144+
var lastStoneWeight = function (stones) {
145+
const pq = new MaxPriorityQueue();
146+
for (const v of stones) {
147+
pq.enqueue(v);
148+
}
149+
while (pq.size() > 1) {
150+
const x = pq.dequeue()['priority'];
151+
const y = pq.dequeue()['priority'];
152+
if (x != y) {
153+
pq.enqueue(x - y);
154+
}
155+
}
156+
return pq.isEmpty() ? 0 : pq.dequeue()['priority'];
157+
};
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```
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### **...**
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```

‎solution/1000-1099/1046.Last Stone Weight/Solution.cpp

Lines changed: 4 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -3,13 +3,10 @@ class Solution {
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int lastStoneWeight(vector<int>& stones) {
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priority_queue<int> pq(stones.begin(), stones.end());
55
while (pq.size() > 1) {
6-
int x = pq.top();
7-
pq.pop();
8-
int y = pq.top();
9-
pq.pop();
10-
if (x != y)
11-
pq.push(x - y);
6+
int x = pq.top(); pq.pop();
7+
int y = pq.top(); pq.pop();
8+
if (x != y) pq.push(x - y);
129
}
1310
return pq.empty() ? 0 : pq.top();
1411
}
15-
};
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};

‎solution/1000-1099/1046.Last Stone Weight/Solution.java

Lines changed: 9 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -1,16 +1,16 @@
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class Solution {
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public int lastStoneWeight(int[] stones) {
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Queue<Integer> queue = new PriorityQueue<>(Comparator.reverseOrder());
4-
for (int stone : stones) {
5-
queue.offer(stone);
3+
PriorityQueue<Integer> q = new PriorityQueue<>((a, b) -> b - a);
4+
for (int v : stones) {
5+
q.offer(v);
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}
7-
while (queue.size() > 1) {
8-
int x = queue.poll();
9-
int y = queue.poll();
7+
while (q.size() > 1) {
8+
int y = q.poll();
9+
int x = q.poll();
1010
if (x != y) {
11-
queue.offer(x - y);
11+
q.offer(y - x);
1212
}
1313
}
14-
return queue.isEmpty() ? 0 : queue.poll();
14+
return q.isEmpty() ? 0 : q.poll();
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}
16-
}
16+
}

‎solution/1000-1099/1046.Last Stone Weight/Solution.js

Lines changed: 18 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,18 @@
1+
/**
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* @param {number[]} stones
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* @return {number}
4+
*/
5+
var lastStoneWeight = function (stones) {
6+
const pq = new MaxPriorityQueue();
7+
for (const v of stones) {
8+
pq.enqueue(v);
9+
}
10+
while (pq.size() > 1) {
11+
const x = pq.dequeue()['priority'];
12+
const y = pq.dequeue()['priority'];
13+
if (x != y) {
14+
pq.enqueue(x - y);
15+
}
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}
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return pq.isEmpty() ? 0 : pq.dequeue()['priority'];
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};

‎solution/1000-1099/1046.Last Stone Weight/Solution.py

Lines changed: 4 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1,9 +1,10 @@
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class Solution:
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def lastStoneWeight(self, stones: List[int]) -> int:
3-
h = [-s for s in stones]
3+
h = [-v for v in stones]
44
heapify(h)
55
while len(h) > 1:
6-
y, x = -heappop(h), -heappop(h)
6+
x = heappop(h)
7+
y = heappop(h)
78
if x != y:
89
heappush(h, x - y)
9-
return 0 if not h else -h[0]
10+
return 0 if len(h) == 0 else -h[0]

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