c*******9
发帖数: 6411 | 1 Write a function int BitSwapReqd(int A, int B) to determine the number of
bits required to convert integer A to integer B.
I have trouble understanding the question, what does it mean to convert
integer A to integer B?
Thanks a lot |
r****t
发帖数: 10904 | 2 function name is the first thing you need to read. |
g**e
发帖数: 6127 | 3 xor一下然后数一下有几个1
【在 c*******9 的大作中提到】
: Write a function int BitSwapReqd(int A, int B) to determine the number of
: bits required to convert integer A to integer B.
: I have trouble understanding the question, what does it mean to convert
: integer A to integer B?
: Thanks a lot
|
e****d
发帖数: 895 | 4 An example to use the compiler to do the calculation.
template struct BIT
{
const static int value = ((M >> N) & 0x01) + BIT::value;
};
template struct BIT
{
const static int value = (M & 0x01);
};
template struct CONVERT
{
const static int value = BIT<(A ^ B), (sizeof(A) - 1)>::value;
};
【在 g**e 的大作中提到】
: xor一下然后数一下有几个1
|
b********h
发帖数: 119 | 5 这个是不是所谓的template meta-programming?
【在 e****d 的大作中提到】
: An example to use the compiler to do the calculation.
: template struct BIT
: {
: const static int value = ((M >> N) & 0x01) + BIT::value;
: };
: template struct BIT
: {
: const static int value = (M & 0x01);
: };
: template struct CONVERT
|
b*****e
发帖数: 474 | 6 Great! Learned something today!
But:int struct CONVERT, should use sizeof(A)*8 instead of sizeof(A), haha
Traditional way:
class BitCounter {
public:
static int convert(int i, int j) { return count(i^j); }
static int count(int k) {
int n = 0;
for (; k != 0; k &= (k-1) ) n++;
return n;
}
};
【在 e****d 的大作中提到】
: An example to use the compiler to do the calculation.
: template struct BIT
: {
: const static int value = ((M >> N) & 0x01) + BIT::value;
: };
: template struct BIT
: {
: const static int value = (M & 0x01);
: };
: template struct CONVERT
|
e****d
发帖数: 895 | 7 Good catch.
【在 b*****e 的大作中提到】
: Great! Learned something today!
: But:int struct CONVERT, should use sizeof(A)*8 instead of sizeof(A), haha
: Traditional way:
: class BitCounter {
: public:
: static int convert(int i, int j) { return count(i^j); }
: static int count(int k) {
: int n = 0;
: for (; k != 0; k &= (k-1) ) n++;
: return n;
|
g*********s
发帖数: 1782 | 8 a common mistake to me too...
【在 e****d 的大作中提到】
: Good catch.
|
