奇偶位交换

/*用0xAAAAAAAA与x相与求的奇数位上数字(偶数位上数字为0)
用0x 55555555 与x相与求的偶数位上数字(奇数位上数字为0)
oddVal右移一位 even左移一位相加即可。*/
class Exchange {
public:
    int exchangeOddEven(int x) {
        // write code here
        int oddVal = (x & 0xAAAAAAAA); // bit 1 3 5 ... 31
        int evenVal = (x & 0x55555555); // bit 0 2 4 ... 30
        return (oddVal >> 1) + (evenVal << 1);
    }
};