Problem 165: Remove duplicates from array

Author: mandliya

README.md

@@ -235,5 +235,6 @@ Include contains single header implementation of data structures and some algori
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+|Given a sorted array, remove duplicates in place and return the new length. It doesn't matter what is in array beyond the unique elements size. Expected O(1) space and O(n) time complexity.| [remove_duplicates.cpp](leet_code_problems/remove_duplicates.cpp) |
 
 

leet_code_problems/remove_duplicates.cpp

@@ -0,0 +1,49 @@
+/*
+ * Given a sorted array, remove duplicates in place and return the new length.
+ * It doesn't matter what is in array beyond the unique elements size.
+ * Expected O(1) space and O(n) time complexity.
+ * Input : {1, 1, 2, 2, 3, 4, 4, 4, 5, 5, 6, 7, 7}
+ * Output: {1, 2, 3, 4, 5, 6, 7}
+ */
+
+#include <iostream>
+#include <vector>
+
+
+template <typename T>
+void swap(T& a, T& b)
+{
+    T c(std::move(a));
+    a = std::move(b);
+    b = std::move(c);
+}
+
+unsigned int remove_duplicates(std::vector<int>& nums)
+{
+    unsigned int i = 0;
+    for (unsigned int j = 0; j < nums.size(); ++j) {
+        if (nums[i] != nums[j]) {
+            swap(nums[++i], nums[j]);
+        }
+    }
+    return i+1;
+}
+
+void print_vector(const std::vector<int>& vec, unsigned int n)
+{
+    for (unsigned int i = 0; i < n; ++i) {
+        std::cout <<  vec[i] << " ";
+    }
+    std::cout << std::endl;
+}
+
+int main()
+{
+    std::vector<int> vec{1, 1, 2, 2, 3, 4, 4, 4, 5, 5, 6, 7, 7};
+    std::cout << "Original vector:";
+    print_vector(vec, vec.size());
+    unsigned int size = remove_duplicates(vec);
+    std::cout << "Output vector:";
+    print_vector(vec, size);
+    return 0;
+}