添加仓库代码

0001-Two-Sum/cpp-0001/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.5)
+project(cpp_0001)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+
+set(SOURCE_FILES main2.cpp)
+add_executable(cpp_0001 ${SOURCE_FILES})

0001-Two-Sum/cpp-0001/main.cpp

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+/// Brute Force
+/// Time Complexity: O(n^2)
+/// Space Complexity: O(1)
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+
+        for(int i = 0 ; i < nums.size() ; i ++)
+            for(int j = i + 1 ; j < nums.size() ; j ++)
+                if(nums[i] + nums[j] == target){
+                    int res[] = {i, j};
+                    return vector<int>(res, res + 2);
+                }
+
+        throw invalid_argument("the input has no solution");
+    }
+};
+
+
+void printVec(const vector<int>& vec){
+    for(int e: vec)
+        cout << e << " ";
+    cout << endl;
+}
+
+int main() {
+
+    const int nums[] = {0,4,3,0};
+    vector<int> nums_vec( nums, nums + sizeof(nums)/sizeof(int) );
+    int target = 0;
+    printVec(Solution().twoSum(nums_vec, target));
+
+    return 0;
+}

0001-Two-Sum/cpp-0001/main2.cpp

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+#include <iostream>
+#include <vector>
+#include <cassert>
+#include <unordered_map>
+
+using namespace std;
+
+/// Two-Pass Hash Table
+/// Time Complexity: O(n)
+/// Space Complexity: O(n)
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+
+        unordered_map<int,int> record;
+        for(int i = 0 ; i < nums.size() ; i ++)
+            record[nums[i]] = i;
+
+        for(int i = 0 ; i < nums.size() ; i ++){
+            unordered_map<int,int>::iterator iter = record.find(target - nums[i]);
+            if(iter != record.end() && iter->second != i){
+                int res[] = {i, iter->second};
+                return vector<int>(res, res + 2);
+            }
+        }
+
+        throw invalid_argument("the input has no solution");
+    }
+};
+
+
+void printVec(const vector<int>& vec){
+    for(int e: vec)
+        cout << e << " ";
+    cout << endl;
+}
+
+int main() {
+
+    const int nums[] = {0,4,3,0};
+    vector<int> nums_vec( nums, nums + sizeof(nums)/sizeof(int) );
+    int target = 0;
+    printVec(Solution().twoSum(nums_vec, target));
+
+    return 0;
+}

0001-Two-Sum/cpp-0001/main3.cpp

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+#include <iostream>
+#include <vector>
+#include <cassert>
+#include <unordered_map>
+
+using namespace std;
+
+/// One-Pass Hash Table
+/// Time Complexity: O(n)
+/// Space Complexity: O(n)
+class Solution {
+public:
+    vector<int> twoSum(vector<int>& nums, int target) {
+
+        unordered_map<int,int> record;
+        for(int i = 0 ; i < nums.size() ; i ++){
+
+            int complement = target - nums[i];
+            if(record.find(complement) != record.end()){
+                int res[] = {i, record[complement]};
+                return vector<int>(res, res + 2);
+            }
+
+            record[nums[i]] = i;
+        }
+
+        throw invalid_argument("the input has no solution");
+    }
+};
+
+
+void printVec(const vector<int>& vec){
+    for(int e: vec)
+        cout << e << " ";
+    cout << endl;
+}
+
+int main() {
+
+    const int nums[] = {0,4,3,0};
+    vector<int> nums_vec( nums, nums + sizeof(nums)/sizeof(int) );
+    int target = 0;
+    printVec(Solution().twoSum(nums_vec, target));
+
+    return 0;
+}

0001-Two-Sum/java-0001/src/Solution1.java

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+import java.util.HashMap;
+
+/// Brute Force
+/// Time Complexity: O(n^2)
+/// Space Complexity: O(1)
+public class Solution1 {
+
+    public int[] twoSum(int[] nums, int target) {
+
+        for(int i = 0 ; i < nums.length; i ++)
+            for(int j = 0 ; j < nums.length ; j ++)
+                if(nums[i] + nums[j] == target){
+                    int[] res = {i, j};
+                    return res;
+                }
+
+        throw new IllegalStateException("the input has no solution");
+    }
+
+    private static void printArr(int[] nums){
+        for(int num: nums)
+            System.out.print(num + " ");
+        System.out.println();
+    }
+
+    public static void main(String[] args) {
+
+        int[] nums = {0, 4, 3, 0};
+        int target = 0;
+        printArr((new Solution1()).twoSum(nums, target));
+    }
+}

0001-Two-Sum/java-0001/src/Solution2.java

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+import java.util.HashMap;
+
+/// Two-Pass Hash Table
+/// Time Complexity: O(n)
+/// Space Complexity: O(n)
+public class Solution2 {
+
+    public int[] twoSum(int[] nums, int target) {
+
+        HashMap<Integer, Integer> record = new HashMap<Integer, Integer>();
+        for(int i = 0 ; i < nums.length ; i ++)
+            record.put(nums[i], i);
+
+        for(int i = 0 ; i < nums.length; i ++){
+
+            Integer index = record.get(target - nums[i]);
+            if(index != null && index != i){
+                int[] res = {i, index};
+                return res;
+            }
+
+            record.put(nums[i], i);
+        }
+
+        throw new IllegalStateException("the input has no solution");
+    }
+
+    private static void printArr(int[] nums){
+        for(int num: nums)
+            System.out.print(num + " ");
+        System.out.println();
+    }
+
+    public static void main(String[] args) {
+
+        int[] nums = {0, 4, 3, 0};
+        int target = 0;
+        printArr((new Solution2()).twoSum(nums, target));
+    }
+}

0001-Two-Sum/java-0001/src/Solution3.java

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+/// Source : https://leetcode.com/problems/two-sum/description/
+/// Author : liuyubobobo
+/// Time   : 2017-11-15
+
+import java.util.HashMap;
+
+/// One-Pass Hash Table
+/// Time Complexity: O(n)
+/// Space Complexity: O(n)
+public class Solution3 {
+
+    public int[] twoSum(int[] nums, int target) {
+
+        HashMap<Integer, Integer> record = new HashMap<Integer, Integer>();
+        for(int i = 0 ; i < nums.length; i ++){
+
+            int complement = target - nums[i];
+            if(record.containsKey(complement)){
+                int[] res = {i, record.get(complement)};
+                return res;
+            }
+
+            record.put(nums[i], i);
+        }
+
+        throw new IllegalStateException("the input has no solution");
+    }
+
+    private static void printArr(int[] nums){
+        for(int num: nums)
+            System.out.print(num + " ");
+        System.out.println();
+    }
+
+    public static void main(String[] args) {
+
+        int[] nums = {0, 4, 3, 0};
+        int target = 0;
+        printArr((new Solution3()).twoSum(nums, target));
+    }
+}

0019-Remove-Nth-Node-From-End-of-List/cpp-0019/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.5)
+project(cpp_0019)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+
+set(SOURCE_FILES main.cpp)
+add_executable(cpp_0019 ${SOURCE_FILES})