Create deque.cpp

Author: Zhenchao Gan

C10-Elementary-Data-Structures/exercise_code/deque.cpp

@@ -0,0 +1,68 @@
+#include<cassert>
+#include<iostream>
+#include<vector>
+
+using namespace std;
+
+class Deque {
+    
+private:
+    vector<int> data_;
+    int size_;
+    int head_;
+    int tail_;
+    int capacity_;
+    
+public:
+    
+    Deque(int size) : size_(0), head_(0), tail_(size-1), capacity_(size), data_(size, 0) {}
+    
+    void push_front(int v) {
+        assert(head_ <= tail_);
+        data_[head_++] = v;
+        size_++;
+    }
+    
+    void push_back(int v) {
+        assert(head_ <= tail_);
+        data_[tail_--] = v;
+        size_++;
+    }
+    
+    void pop_front() {
+        assert(head_ > 0);
+        head_--;
+        size_--;
+    }
+    
+    void pop_back() {
+        assert(tail_ < capacity_);
+        tail_++;
+        size_--;
+    }
+    
+    int front() const { 
+        assert(head_ > 0);
+        return data_[head_-1];
+    }
+    
+    int back() const {
+        assert(tail_ < capacity_-1);
+        return data_[tail_+1];
+    }
+    
+    int size() const { return size_; }
+    
+    int empty() const { return size_ == 0; }
+    
+    
+    ~Deque() {}
+};
+
+int main() {
+    Deque mydeque(3);
+    mydeque.push_front(1);
+    mydeque.push_back(3);
+    cout << mydeque.front() << " " << mydeque.back() << endl;
+    cout << mydeque.size();
+}