2015-09-09 [Little information]--data capture and processing engineer--3 face

Time: 2015-09-09 13:40 ~ 14:40

Location: No. 1th, Wang Zhuang Road, Haidian District , Beijing Tongfang Science and Technology Plaza, Block D, West 7

1. How many bits a and B are different

#include <climits>#include<cmath>#include<cstdlib>#include<cstring>#include<iostream>#include<iomanip>#include<string>using namespacestd;//Return the number of difference bits of a and B//Return 1 If a = 0 and B = 1//Return 2 If a = 0 and B = 3intDiffintAintb) {    intAns =0; A= a ^b; inti = +; intj =1;  while(i--) {        if(A &j) Ans++; J<<=1; }    returnans;}intMain () {Const structTestCase {intA; intb; intret; } test_cases[]= {        { 0,1,1 },        { 0,2,1 },        { 0,3,2 },        { 1,3,1 },        { -1,0, + },        { -1,3, - },        { -1,0x7FFFFFFF,1 },    };  for(intIII =0; III <sizeof(test_cases)/sizeof(TestCase); iii++) {        ConstTestCase &AMP;TC =TEST_CASES[III]; Const intActual_ret =diff (TC.A, tc.b); if(Tc.ret! =Actual_ret) {cout<<"Case #"<< III <<": FAILED"<<Endl; cout<<"\texpected ret="<< Tc.ret <<Endl; cout<<"\tacutal ret="<< Actual_ret <<Endl; }    }    return 0;}

2. grep finds the first line

grep "What_you_want" Target_file | Head-n 1

3. Find the first log of a day in a 100GB file

The practical application of binary search requires attention to robustness.

2015-09-09 [Little information]--data capture and processing engineer--3 face