使用按位运算符[closed]交换整数中的第一位和最后一位

int digits = log10(x)

int first = x / pow(10,digits)

int last = x % 10

int swapped = x + (last - first) * pow(10,digits) + (first - last)

def swap_digit(n):
    x = str(n)
    if len(x) < 2:
        return x
    return  int(x[-1] + x[1:-1] + x[0])

#include <stdio.h>
#include <string.h>

int main()
{
    int n = 123456789;

    char buf[100];
    int r = snprintf(buf, sizeof(buf), \"%d\", n);
    char t = buf[0];
    buf[0] = buf[r-1];
    buf[r-1] = t;
    int swap;
    sscanf(buf, \"%d\", &swap);

    printf(\"n = %d,  swap = %d\\n\", n, swap);

    return 0;
}

def swap(i):
    s = list(str(i))
    s[0], s[-1] = s[-1], s[0]
    i = int(\'\'.join(s))
    return i

print swap(123456789) # 923456781