#include <stdio.h>

int main()
{
	char S[10], A[10] = { 'y','u','k','i','c','o','d','e','r','\0' };
	scanf("%s", S);

	for (int i = 0; i < 9; i++)
	{
		if (S[i] == A[i])
		{
			continue;
		}

		printf("%c", A[i]);
		break;
	}

	return 0;
}