腾讯面试题：位运算——用位存储40亿个40亿以内的整数

#include <iostream>  

namespace std;  

   3:   

// 能表示42亿+的无符号整数  

   5:  

//数组长度,0-40亿  

const Bit32 thirtytwo=32;  

   8:    

void createArray(Bit32 *&arr)  

  10: {  

new Bit32[maxLen];  

sizeof(arr));  

  13: }  

  14:  

bool setBit(Bit32 *arr,Bit32 num)  

  16: {  

if(((arr[num/thirtytwo])&(1<<(thirtytwo-num%thirtytwo-1)))==0)  

  18:   {  

  19:      arr[num/thirtytwo]|=1<<(thirtytwo-num%thirtytwo-1);  

return true;  

  21:   }  

else  

  23:   {  

return false;  

  25:    }  

  26: }  

  27:   

int main()  

  29: {  

  30:    Bit32 *s;  

  31:    createArray(s);  

if(!setBit(s,5))  

  33:    {  

<<endl;  

  35:    }  

if(!setBit(s,64))  

  37:    {  

<<endl;  

  39:    }  

if(!setBit(s,1))  

  41:    {  

<<endl;  

  43:    }  

  44:  

return 0;  

  46: }