Implementation of bitmaps

#include <iostream>using namespace std; #include <vector>class bitmap{public:bitmap (): _size (0) {}bitmap ( size_t size): _size (0) {_array.resize ((size>>5) +1);} void Set (size_t num) {size_t index=num>>5;//This is the first byte of the request size_t n=num%32;//which bits _array[index]|= of a byte (1<<n) ;} void Reset (size_t num) {size_t index=num>>5;size_t n=num%32;_array[index]&=~ (1<<n);} BOOL Test (size_t num) {size_t index=num>>5;size_t n=num%32;return _array[index]& (1<<n);} private:vector<size_t> _array;//array size_t _size;//number};

The above is the simple application of bitmaps, bitmaps are widely used, we should pay attention to understanding!

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Implementation of bitmaps