#include<stdio.h>
int main(void)
{
  char s1[101];
  char s2[101];
  unsigned long long int p1,p2;
  char x1,x2;

  scanf("%s %llu %c",s1,&p1,&x1);
  scanf("%s %llu %c",s2,&p2,&x2);

  if(p1>p2){
    printf("%s\n",s1);
  }
  else if(p1<p2){
    printf("%s\n",s2);
  }
  else{
    printf("-1\n");
  }
  return 0;
}