字符串中16进制数字转换成十进制输出

void main(){

for (int i = 0; str[i] != '\0'; i++){
if (str[i] >= '0'&&str[i] <= '9'){
n = 16 * n + str[i] - '0';
}
else{
n = 16 * n + str[i] - 'a' + 10;
}
}
printf("转换后的数字是：%d\n", n);

}