#include <stdio.h>
#include <string.h>
int main(){
char znaki[20];
char haslo[10];
while(1)
{
fgets(znaki, 20, stdin);
if((int)znaki[0]==10) break;
int j=0;
for(int i=0; i<20; i+=2)
{
haslo[j]=znaki[i]-65;
j++;
}
j=0;
for(int i=1; i<20; i+=2)
{
haslo[j]+=(znaki[i]-65)*16;
printf("%c", haslo[j]);
j++;
}
printf("\n");
}
return 0;
}
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