基础练习 十六进制转十进制

#include<cstdio>
#include<cmath>
#include<cstring>

int main()
{
    int len, i, t;
    long long int N = 0;
    char w[8];
    gets(w);
    len = strlen(w);
    for(i = 0; w[i] != '\0'; i++)
    {
        switch(w[i])
        {
            case'A': t = 10; break;
            case'B': t = 11; break;
            case'C': t = 12; break;
            case'D': t = 13; break;
            case'E': t = 14; break;
            case'F': t = 15; break;
            default:t = w[i] - '0'; break;
        }
        N = N + t * pow(16, len - 1 - i);
    } 
    printf("%I64d\n", N);
    return 0;
}