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# template<class T> # class MinHeap { # public: # MinHeap(int MinHeapSize = 10); # ~MinHeap() {delete [] heap;} # int Size() const {return CurrentSize;} # T Min() {if (CurrentSize == 0) # throw OutOfBounds(); # return heap[1];} # MinHeap<T>& Insert(const T& x); # MinHeap<T>& DeleteMin(T& x); # void Initialize(T a[], int size, int ArraySize); # void Deactivate() {heap = 0;} # void Output() const; # private: # int CurrentSize, MaxSize; # T *heap; # }; # # template<class T> # MinHeap<T>::MinHeap(int MinHeapSize) # { # MaxSize = MinHeapSize; # heap = new T[MaxSize+1]; # CurrentSize = 0; # } # # template<class T> # MinHeap<T>& MinHeap<T>::Insert(const T& x) # { # if (CurrentSize == MaxSize) # throw NoMem(); # # //为x寻找应插入的位置 # //i从新的叶节点开始，并沿着树上升 # int i = ++CurrentSize; # while (i != 1 && x < heap[i/2]) # { # heap[i] = heap[i/2]; // 将元素下移 # i /= 2; // 移向父节点 # } # heap[i] = x; # # return *this; # } # # template<class T> # MinHeap<T>& MinHeap<T>::DeleteMin(T& x) # { # if (CurrentSize == 0) # throw OutOfBounds(); # # x = heap[1]; # # T y = heap[CurrentSize--]; //最后一个元素 # # // 从根开始, 为y寻找合适的位置 # int i = 1, // 堆的当前节点 # ci = 2; // i的子节点 # # while (ci <= CurrentSize) # { # // 使heap[ci] 是i较小的子节点 # if (ci < CurrentSize # && heap[ci] > heap[ci+1]) # ci++; # # // 能把y放入heap[i]吗? # if (y <= heap[ci]) # break; // 能 # # // 不能 # heap[i] = heap[ci]; // 子节点上移 # i = ci; // 下移一层 # ci *= 2; # } # # heap[i] = y; # # return *this; # } # # template<class T> # void MinHeap<T>::Initialize(T a[], int size, int ArraySize) # { # delete [] heap; # heap = a; # CurrentSize = size; # MaxSize = ArraySize; # # // 产生一个最小堆 # for (int i = CurrentSize/2; i >= 1; i--) # { # T y = heap[i]; // 子树的根 # # // 寻找放置y的位置 # int c = 2*i; // c 的父节点是y的目标位置 # # while (c <= CurrentSize) # { # // 使heap[c]是较小的子节点 # if (c < CurrentSize && # heap[c] > heap[c+1]) c++; # # // 能把y放入heap[c/2]吗? # if (y <= heap[c]) break; // 能 # # // 不能 # heap[c/2] = heap[c]; // 子节点上移 # c *= 2; // 下移一层 # } # # heap[c/2] = y; # } # } # # template<class T> # void MinHeap<T>::Output() const # { # cout << "The " << CurrentSize # << " elements are"<< endl; # for (int i = 1; i <= CurrentSize; i++) # cout << heap[i] << ' '; # cout << endl; # } #