add Contains Duplicate solution

Crayzero · Crayzero · commit b52bc4c3686d · 2015-06-17T20:20:32.000+08:00
diff --git a/Solutions/Contains Duplicate/main.cpp b/Solutions/Contains Duplicate/main.cpp
@@ -0,0 +1,61 @@
+#include <iostream>
+#include <unordered_set>
+#include <vector>
+#include <unordered_map>
+#include <algorithm>
+#include <map>
+using namespace std;
+
+class Solution {
+public:
+    bool containsDuplicate(vector<int>& nums) {
+        unordered_set<int> set;
+        for(auto iter = nums.begin(); iter != nums.end(); iter++) {
+            if (set.find(*iter) == set.end())
+                set.insert(*iter);
+            else
+                return true;
+        }
+        return false;
+    }
+    bool containsNearbyDuplicate(vector<int>& nums, int k) {
+        unordered_map<int, int> m;
+        for(int i = 0; i <= k && i < nums.size(); i++) {
+            if (m.find(nums[i]) == m.end())
+                m[nums[i]] = i;
+            else
+                return true;
+        }
+        for(int i = k+1; i < nums.size(); i++) {
+            m.erase(nums[i-k-1]);
+            if (m.find(nums[i]) == m.end())
+                m[nums[i]] = i;
+            else
+                return true;
+        }
+        return false;
+    }
+    bool containsNearbyAlmostDuplicate(vector<int>& nums, int k, int t) {
+        map<int, int> m;
+        int left = 0;
+        int right = 0;
+        for (; right < nums.size(); right++) {
+            if (right - left > k && m.find(nums[left]) != m.end())
+                m.erase(nums[left++]);
+            auto low = m.lower_bound(nums[right] - t);
+            if (low != m.end() && abs(low->first - nums[right]) <= t)
+                return true;
+            m[nums[right]] = right;
+        }
+        return false;
+    }
+};
+
+int main()
+{
+    Solution s;
+    vector<int> nums = {0,1,2,3,4,5,3};
+    //cout<<s.containsDuplicate(nums);
+    cout<<s.containsNearbyDuplicate(nums, 2);
+    return 0;
+}
