#include <stdio.h>
#include<string.h>
#include<math.h>
int main()
{
int diu,a,b,i,m,k,t,r=0;
char s1[1000]={0};
scanf("%d",&b);
fflush(stdin);
for(k=1;k<=b;++k)
{
gets(s1);
for(i=0; i<strlen(s1); ++i)
{
if(('0'<=s1[i]&&s1[i]<='9')||('A'<=s1[i]&&s1[i]<='F')||('a'<=s1[i]&&s1[i]<='f')||(s1[i]=='x'||s1[i]=='X'))
m=1;
else
{
m=0;
break;
}
}
if(m==1)
{
if((s1[0]=='0')&&(s1[1]=='x'||s1[1]=='X'))
{
for(t=2;t<strlen(s1);t++)
{
double l=strlen(s1)-t-1;
double z=pow(16,l);
int w=(int)z;
if('0'<=s1[t]&&s1[t]<='9')
r+=w*(s1[t]-'0');
else if('A'<=s1[t]&&s1[t]<='F')
r+=w*(s1[t]-'A'+10);
else if('a'<=s1[t]&&s1[t]<='f')
r+=w*(s1[t]-'a'+10);
else
{
printf("null");
break;
}
}
if(s1[t]!='x' &&s1[t]!='X')
printf("%d",r);
r=0;
}
else
printf("null");
}
else if(m==0)
{
printf("null");
}
fflush(stdin);
printf("\n");
}
return 0;
}