feat: update solutions to lc/lcof/lcci problem: Majority Element

doocs · Jun 12, 2021 · 4d7d4fa · 4d7d4fa
1 parent b56d67f
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diff --git a/README.md b/README.md
@@ -50,6 +50,7 @@
 
 ### 数组
 
+- [多数元素](./solution/0100-0199/0169.Majority%20Element/README.md)
 - [删除排序数组中的重复项](./solution/0000-0099/0026.Remove%20Duplicates%20from%20Sorted%20Array/README.md)
 - [删除排序数组中的重复项 II](./solution/0000-0099/0080.Remove%20Duplicates%20from%20Sorted%20Array%20II/README.md)
 - [移除元素](./solution/0000-0099/0027.Remove%20Element/README.md)

diff --git a/README_EN.md b/README_EN.md
@@ -50,6 +50,7 @@ Complete solutions to [LeetCode](https://leetcode-cn.com/problemset/all/), [LCOF
 
 ### Arrays
 
+- [Majority Element](./solution/0100-0199/0169.Majority%20Element/README_EN.md)
 - [Remove Duplicates from Sorted Array](./solution/0000-0099/0026.Remove%20Duplicates%20from%20Sorted%20Array/README_EN.md)
 - [Remove Duplicates from Sorted Array II](./solution/0000-0099/0080.Remove%20Duplicates%20from%20Sorted%20Array%20II/README_EN.md)
 - [Remove Element](./solution/0000-0099/0027.Remove%20Element/README_EN.md)

diff --git a/lcci/17.10.Find Majority Element/README.md b/lcci/17.10.Find Majority Element/README.md
@@ -35,7 +35,7 @@
 
 <!-- 这里可写通用的实现逻辑 -->
 
-摩尔投票法
+摩尔投票法。时间复杂度 O(n)，空间复杂度 O(1)。
 
 <!-- tabs:start -->
 
@@ -44,15 +44,37 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```python
-
+class Solution:
+    def majorityElement(self, nums: List[int]) -> int:
+        cnt = major = 0
+        for num in nums:
+            if cnt == 0:
+                major = num
+                cnt = 1
+            else:
+                cnt += (1 if major == num else -1)
+        return major
 ```
 
 ### **Java**
 
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
-
+class Solution {
+    public int majorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
 ```
 
 ### **JavaScript**
@@ -63,23 +85,63 @@
  * @return {number}
  */
 var majorityElement = function(nums) {
-    let candidate = 0, count = 0;
-    for (let num of nums) {
-        if (count == 0) candidate = num;
-        if (candidate == num) {
-            count++;
+    let cnt = 0;
+    let major = 0;
+    for (const num of nums) {
+        if (cnt == 0) {
+            major = num;
+            cnt = 1;
         } else {
-            count--;
+            cnt += (major == num ? 1 : -1);
         }
     }
-    let n = 0;
-    for (let num of nums) {
-        if (candidate == num) n++;
+    return major;
+};
+```
+
+### **C++**
+
+```cpp
+class Solution {
+public:
+    int majorityElement(vector<int>& nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
     }
-    return n > (nums.length / 2) ? candidate : -1;
 };
 ```
 
+### **C#**
+
+```cs
+public class Solution {
+    public int MajorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        foreach (int num in nums)
+        {
+            if (cnt == 0)
+            {
+                major = num;
+                cnt = 1;
+            }
+            else
+            {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
+```
+
 ### **...**
 
 ```

diff --git a/lcci/17.10.Find Majority Element/README_EN.md b/lcci/17.10.Find Majority Element/README_EN.md
@@ -45,13 +45,35 @@ Boyer–Moore majority vote algorithm
 ### **Python3**
 
 ```python
-
+class Solution:
+    def majorityElement(self, nums: List[int]) -> int:
+        cnt = major = 0
+        for num in nums:
+            if cnt == 0:
+                major = num
+                cnt = 1
+            else:
+                cnt += (1 if major == num else -1)
+        return major
 ```
 
 ### **Java**
 
 ```java
-
+class Solution {
+    public int majorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
 ```
 
 ### **JavaScript**
@@ -62,23 +84,63 @@ Boyer–Moore majority vote algorithm
  * @return {number}
  */
 var majorityElement = function(nums) {
-    let candidate = 0, count = 0;
-    for (let num of nums) {
-        if (count == 0) candidate = num;
-        if (candidate == num) {
-            count++;
+    let cnt = 0;
+    let major = 0;
+    for (const num of nums) {
+        if (cnt == 0) {
+            major = num;
+            cnt = 1;
         } else {
-            count--;
+            cnt += (major == num ? 1 : -1);
         }
     }
-    let n = 0;
-    for (let num of nums) {
-        if (candidate == num) n++;
+    return major;
+};
+```
+
+### **C++**
+
+```cpp
+class Solution {
+public:
+    int majorityElement(vector<int>& nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
     }
-    return n > (nums.length / 2) ? candidate : -1;
 };
 ```
 
+### **C#**
+
+```cs
+public class Solution {
+    public int MajorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        foreach (int num in nums)
+        {
+            if (cnt == 0)
+            {
+                major = num;
+                cnt = 1;
+            }
+            else
+            {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
+```
+
 ### **...**
 
 ```

diff --git a/lcci/17.10.Find Majority Element/Solution.cpp b/lcci/17.10.Find Majority Element/Solution.cpp
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    int majorityElement(vector<int>& nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+};
diff --git a/lcci/17.10.Find Majority Element/Solution.cs b/lcci/17.10.Find Majority Element/Solution.cs
@@ -0,0 +1,18 @@
+public class Solution {
+    public int MajorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        foreach (int num in nums)
+        {
+            if (cnt == 0)
+            {
+                major = num;
+                cnt = 1;
+            }
+            else
+            {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
diff --git a/lcci/17.10.Find Majority Element/Solution.go b/lcci/17.10.Find Majority Element/Solution.go
@@ -0,0 +1,16 @@
+func majorityElement(nums []int) int {
+    var cnt, major int
+    for _, num := range nums {
+        if cnt == 0 {
+            major = num
+            cnt = 1
+        } else {
+            if major == num {
+                cnt++
+            } else {
+                cnt--
+            }
+        }
+    }
+    return major
+}
diff --git a/lcci/17.10.Find Majority Element/Solution.java b/lcci/17.10.Find Majority Element/Solution.java
@@ -0,0 +1,14 @@
+class Solution {
+    public int majorityElement(int[] nums) {
+        int cnt = 0, major = 0;
+        for (int num : nums) {
+            if (cnt == 0) {
+                major = num;
+                cnt = 1;
+            } else {
+                cnt += (major == num ? 1 : -1);
+            }
+        }
+        return major;
+    }
+}
diff --git a/lcci/17.10.Find Majority Element/Solution.js b/lcci/17.10.Find Majority Element/Solution.js
@@ -3,18 +3,15 @@
  * @return {number}
  */
  var majorityElement = function(nums) {
-    let candidate = 0, count = 0;
-    for (let num of nums) {
-        if (count == 0) candidate = num;
-        if (candidate == num) {
-            count++;
+    let cnt = 0;
+    let major = 0;
+    for (const num of nums) {
+        if (cnt == 0) {
+            major = num;
+            cnt = 1;
         } else {
-            count--;
+            cnt += (major == num ? 1 : -1);
         }
     }
-    let n = 0;
-    for (let num of nums) {
-        if (candidate == num) n++;
-    }
-    return n > (nums.length / 2) ? candidate : -1;
+    return major;
 };
diff --git a/lcci/17.10.Find Majority Element/Solution.py b/lcci/17.10.Find Majority Element/Solution.py
@@ -0,0 +1,10 @@
+class Solution:
+    def majorityElement(self, nums: List[int]) -> int:
+        cnt = major = 0
+        for num in nums:
+            if cnt == 0:
+                major = num
+                cnt = 1
+            else:
+                cnt += (1 if major == num else -1)
+        return major