练习1

1、用一种算法求9999里面有多少个1

#include<iostream>

#include<stdio.h> using namespace std; int main() { int numBass = 9999; int countNum = 0; int numT[32] = {0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x100,0x200,0x400,0x800,0x1000,0x2000,0x4000,0x10000,0x20000,0x40000, 0x80000,0x100000,0x200000,0x400000,0x800000,0x1000000,0x2000000,0x4000000,0x8000000,0x10000000,0x20000000,0x40000000,0x80000000}; for(int i = 0;i<32;i++) { if(numBass&numT[i] > 0) { countNum++; } numBass = numBass>>1; } cout<<countNum<<endl; return 0; }