#include <stdio.h>
#include <string.h>

typedef char PVARIETY[32];

typedef struct RCELL *RLIST;
struct RCELL {
	PVARIETY variety;
	PVARIETY pollinizer;
	RLIST next;
};

typedef struct PCELL *PLIST;
struct PCELL {
	PVARIETY pollinizer;
	PLIST next;
};

PLIST lookup(PVARIETY a, RLIST L)
{
	PLIST P;

	if (L == NULL)
		return NULL;
	else if (!strcmp(L->variety, a)) /* L->variety == a */ {
		P = (PLIST) malloc(sizeof(struct PCELL));
		strcpy(P->pollinizer, L->pollinizer);
		P->next = lookup(a, L->next);
		return P;
	}
	else /* a not the domain value of current pair */
		return lookup(a, L->next);
}