[1. TwoSum] solution by using hash map

Author: YILING

LeetCode.xcodeproj/project.pbxproj

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LeetCode.xcodeproj/xcuserdata/YLibrarian.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist

@@ -0,0 +1,71 @@
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+<Bucket
+   type = "1"
+   version = "2.0">
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+      <BreakpointProxy
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+            endingLineNumber = "30"
+            landmarkName = "TwoSum::twoSum(std::vector&lt;int&gt; &amp;nums, int target)"
+            landmarkType = "7">
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LeetCode/1_two_sum.cpp

@@ -0,0 +1,33 @@
+//
+//  1_two_sum.cpp
+//  LeetCode
+//
+//  Created by Yi-Ling Wu on 12/03/2017.
+//  Copyright © 2017 YILING. All rights reserved.
+//
+
+#include "iostream"
+#include "1_two_sum.hpp"
+#include <unordered_map>
+
+std::vector<int> TwoSum::twoSum(std::vector<int> &nums, int target) {
+    std::unordered_map<int, int> hash;
+    std::vector<int> result;
+    for (int i = 0; i < nums.size(); i++) {
+        if (hash.find(target - nums[i]) != hash.end()) {
+            result.push_back(hash[target - nums[i]]);
+            result.push_back(i);
+            std::cout << i << std::endl;
+            std::cout << result[i] << std::endl;
+            return result;
+        }
+
+        hash[nums[i]] = i;
+        std::cout << hash[i] << std::endl;
+    }
+
+    // 无解的情况
+    result.push_back(-1);
+    result.push_back(-1);
+    return result;
+}

LeetCode/1_two_sum.hpp

@@ -0,0 +1,30 @@
+//
+//  1_two_sum.hpp
+//  LeetCode
+//
+//  Created by Yi-Ling Wu on 12/03/2017.
+//  Copyright © 2017 YILING. All rights reserved.
+//
+
+// Question: Given an array of integers, return indices of the two numbers such that they add up to a specific target. \
+    You may assume that each input would have exactly one solution, and you may not use the same element twice. \
+
+/*Example:
+ Given nums = [2, 7, 11, 15], target = 9,
+
+ Because nums[0] + nums[1] = 2 + 7 = 9,
+ return [0, 1]. */
+
+#ifndef __two_sum_hpp
+#define __two_sum_hpp
+
+#include <stdio.h>
+#include <vector>
+
+class TwoSum {
+public:
+    std::vector<int> twoSum(std::vector<int> &nums, int target);
+};
+
+
+#endif /* __two_sum_hpp */

LeetCode/main.cpp

@@ -7,9 +7,15 @@
 //
 
 #include <iostream>
+#include "1_two_sum.hpp"
 
 int main(int argc, const char * argv[]) {
-    // insert code here...
-    std::cout << "Hello, World!\n";
+
+    // Test_1: TwoSum
+    TwoSum *twosum = new TwoSum;
+    std::vector<int> nums = {3,2,4};
+    int target = 6;
+    std::vector<int> result = twosum->twoSum(nums, target);
     return 0;
+    
 }

build/Debug/LeetCode

@@ -0,0 +1,3 @@
+dependencies: \
+  /Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/LeetCode/1_two_sum.cpp \
+  /Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/LeetCode/1_two_sum.hpp

build/LeetCode.build/Debug/LeetCode.build/LeetCode-all-non-framework-target-headers.hmap

@@ -0,0 +1,2 @@
+/Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/build/LeetCode.build/Debug/LeetCode.build/Objects-normal/x86_64/1_two_sum.o
+/Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/build/LeetCode.build/Debug/LeetCode.build/Objects-normal/x86_64/main.o

build/LeetCode.build/Debug/LeetCode.build/LeetCode-all-target-headers.hmap

@@ -0,0 +1,3 @@
+dependencies: \
+  /Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/LeetCode/main.cpp \
+  /Users/YLibrarian/Developer/Leetcode/Algorithm_1/LeetCode/LeetCode/1_two_sum.hpp