solution 217-Contains-Duplicate

Author: andy6804tw

Algorithms/C/217-Contains-Duplicate.md

@@ -0,0 +1,30 @@
+# 217. Contains Duplicate (C Language)
+
+## Problem
+
+Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
+
+
+
+##### Solution 1.
+
+使用C語言的qsort()來排序，再逐一搜尋是有存在重複元素。
+
+- 字串處理
+- Run Time: 12 ms
+- 時間複雜度: O(nlogn)
+- 空間複雜度: O(1)
+
+```c
+int comp (const void * a, const void * b) {
+   return ( *(int*)a - *(int*)b );
+}
+
+bool containsDuplicate(int* nums, int numsSize) {
+    qsort(nums, numsSize, sizeof(int), comp);
+    for (int i = 0; i < numsSize - 1; i++) {
+        if (nums[i] == nums[i+1]) return true;
+    }
+    return false;
+}
+```

Algorithms/Java/217-Contains-Duplicate.md

@@ -0,0 +1,45 @@
+# 217. Contains Duplicate (Java)
+
+## Problem
+
+Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
+
+
+
+##### Solution 1.
+
+使用 Set 容器來記錄每個值，Set 是一個集合會自動拋棄重複數字。
+
+- 字串處理
+- Run Time: 16 ms
+- 時間複雜度: O(n)
+- 空間複雜度: O(n)
+
+```java
+class Solution {
+    public boolean containsDuplicate(int[] nums) {
+        Set<Integer> set =new HashSet<>();
+        for(int i=0;i<nums.length;i++) {
+        		set.add(nums[i]);
+        }
+        return nums.length != set.size();
+    }
+}
+```
+
+##### Solution 2.
+
+使用 Arrays.stream() 的d istinct() 找出不重複的數值數量。
+
+- 字串處理
+- Run Time: 16 ms
+- 時間複雜度: O(n)
+- 空間複雜度: O(1)
+
+```java
+class Solution {
+    public boolean containsDuplicate(int[] nums) {
+        return Arrays.stream(nums).distinct().toArray().length != nums.length;
+    }
+}
+```

README.md

@@ -25,6 +25,7 @@
 171.|[Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/description/)|Math|Easy|[C](/Algorithms/C/171-Excel-Sheet-Column-Number.md) [Java](/Algorithms/Java/171-Excel-Sheet-Column-Number.md)|
 198.|[House Robber](https://leetcode.com/problems/house-robber/description/)|Array|Easy|[C](/Algorithms/C/198-House-Robber.md) [Java](/Algorithms/Java/198-House-Robber.md)|
 205.|[Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/description/)|Array|Easy|[C](/Algorithms/C/205-Isomorphic-Strings.md) [Java](/Algorithms/Java/205-Isomorphic-Strings.md)|
+217.|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/description/)|Array|Easy|[C](/Algorithms/C/217-Contains-Duplicate.md) [Java](/Algorithms/Java/217-Contains-Duplicate.md)|
 242.|[Valid Anagram](https://leetcode.com/problems/valid-anagram/description/)|String|Easy|[C](/Algorithms/C/242-Valid-Anagram.md) [Java](/Algorithms/Java/242-Valid-Anagram.md)|
 283.|[Move Zeroes](https://leetcode.com/problems/move-zeroes/description/)|Array|Easy|[C](/Algorithms/C/283-Move-Zeroes.md) [Java](/Algorithms/Java/283-Move-Zeroes.md)|
 292.|[Nim Game](https://leetcode.com/problems/nim-game/description/)|Math|Easy|[C](/Algorithms/C/292-Nim-Game.md) [Java](/Algorithms/Java/292-Nim-Game.md)|

compiler/C/Main.c

@@ -3,25 +3,29 @@
 #include <string.h>
 #include <math.h>
 typedef int bool;
-int *twoSum(int *numbers, int numbersSize, int target, int *returnSize);
+bool containsDuplicate(int *nums, int numsSize);
 int main()
 {
-  int arr[] = {2, 3, 4, 5, 6};
-  printf("%d\n", twoSum(arr, 5,8,arr)[0]);
+  int arr[] = {0};
+  printf("%d\n", containsDuplicate(arr,1));
 }
-int *twoSum(int *numbers, int numbersSize, int target, int *returnSize){
-  int arr[100000] = {0}, i = 0, *ans=(int*)calloc(2,sizeof(int));
-  for(i=0;i<numbersSize;i++)
-  {
-    if (arr[target - numbers[i]+1000] > 0)
-    {
-      ans[0] = i + 1 > arr[target - numbers[i] + 1000] ? arr[target - numbers[i] + 1000] : i + 1;
-      ans[1] = i + 1 < arr[target - numbers[i] + 1000] ? arr[target - numbers[i] + 1000] : i + 1;
-      break;
-    }else{
-      arr[numbers[i] + 1000] = i + 1;
+bool containsDuplicate(int *nums, int numsSize)
+{
+  int i=0,j=0,count=0,num=-1;
+  for(i=0;i<numsSize;i++){
+    for(j=i+1;j<numsSize;j++){
+      if(nums[i]>nums[j]){
+        int temp=nums[i];
+        nums[i]=nums[j];
+        nums[j]=temp;
+      }
+    }
+  }
+  for(i=0;i<numsSize;i++){
+    if(num!=nums[i]){
+      count++;
+      num=nums[i];
     }
   }
-  *returnSize=2;
-  return ans;
+  return numsSize != count;
 }