题解 | #进制转换#

#include <stdio.h>

int main() { char str[128] = {0}; int out = 0; int num = -1;

while(gets(str))	//输入0XAB
{
	//str[0] = '0' str[1] = 'X' str[2] = 'A' str[3] = 'B'
    for(int i = strlen(str)-1; i > 1; i--)
    {
        num++;
        if(str[i] >= 'a' && str[i] <= 'f') 
        {
            out += (str[i] - 'a' + 10) * pow(16, num);
        }
        else if(str[i] >= 'A' && str[i] <= 'F')
        {
            out += (str[i] - 'A' + 10) * pow(16, num);
        }
        else if(str[i] >= '0' && str[i] <= '9')
        {
            out += (str[i] - '0') * pow(16, num);
        }
        else
        {
            printf("data failed!!!\n");
            return -1;
        }
    }
    printf("%d\n", out);
}
return 0;

}