[2220] Minimum Bit Flips to Convert Number

咦 XD 用直覺的想法寫了果然笨笨的！！！

看了別人的超速解法結果看不懂！

但exclusive or 的部份還是很好用XD

拿來改一下就也變快了～～～～～

#if 0 //原本笨方法

int minBitFlips(int start, int goal){

int big=0,small=0, count=0;

big = (start > goal)? start: goal ;

small = (start > goal)? goal: start;

while (big>0)

{

int modBig= big%2;

int modSmall= small%2;

if (modBig!=modSmall)

count++;

big = big>>1;

small=small >>1;

}

return count;

}

#else //原來先XOR一下再去算有幾個1就好了！！！

int minBitFlips(int start, int goal){

int check = start ^ goal;

int count = 0;

while (check >0)

{

if (check%2==1)

count++;

check = check >>1 ;

}

return count;

}

#endif