#include <stdio.h>
#define MAXLEN 256
#define SIZE 5

int getDigits(int i) {
  int count = 0;
  do {
    i /= 10;
    count++;
  } while (i);

  return count;
}

int main(void) {
  // remember to initialize to 0
  int matrix[SIZE][SIZE] = {};
  int liked[SIZE][SIZE] = {};

  char buf[MAXLEN];
  fgets(buf, MAXLEN, stdin);
  int offset = 0;
  int src, dist;

  while (sscanf(buf + offset, "%d,%d,", &src, &dist) != EOF) {
    // printf("%d -> %d\n", src, dist);
    offset += getDigits(src) + getDigits(dist) + 2;
    matrix[src][dist] = 1;
  }

  // calculate likes
  for (int i = 0; i < SIZE; i++) {
    int count = 0;
    for (int j = 0; j < SIZE; j++) {
      if (matrix[i][j] == 1) {
        if (++count % 2 == 1) {
          // printf("%d liked %d, count: %d\n", i, j, count);
          liked[i][j] = 1;
        }
      }
    }
  }

  scanf("%d", &dist);

  int hasLikes = 0;
  for (int i = 0; i < SIZE; i++) {
    if (liked[i][dist] == 1) {
      hasLikes = 1;
      printf("%d,", i);
    }
  }

  if (!hasLikes) {
    printf("-1");
  }

  return 0;
}