#include<stdlib.h>
#include<stdio.h>

struct ahel {
	char *str;
	struct ahel *next;
} ;

void addtoahel(struct ahel**);
void delfromahel(struct ahel**);
void findfromahel(struct ahel*);
char *getstring(void);

int main() {
	struct ahel *loend = NULL;
	int exxit = 0;
	char input[81];

	while(!exxit) {
		printf("\n\t(L)isa string\n\t(E)emalda stringn\n\t(O)tsi stringi\n\t(S)ure maha\n\nValik: ");
		
		fgets(input, 81, stdin);
		if(input[0] > 90)
			input[0] -= 32;
		if(input[0] == 'L')
			addtoahel(&loend);
		else if(input[0] == 'E')
			delfromahel(&loend);
		else if(input[0] == 'O')
			findfromahel(loend);
		else if(input[0] == 'S')
			exxit = 1;
	}

	return 0;
}

// buffer - tehakse malloc. hoiduda leketest.
void addtoahel(struct ahel **loend) {
	struct ahel *abi;
	if(*loend == NULL) {
		*loend = malloc(sizeof(struct ahel*));
		abi = *loend;
	}
	else {
		abi = *loend;
		while(abi->next != NULL)
			abi = abi->next;
		abi = abi->next = malloc(sizeof (struct ahel*));
	}
	
	printf("Sisestage string: ");

	abi->str = getstring();
	abi->next = NULL;

	return;
}

void delfromahel(struct ahel **loend) {
	int i, d;
	struct ahel *abi, *abii;
	
	if(*loend == NULL) {
		printf("Ahelloend on tyhi!\n");
		return;
	}
	
	abi = *loend;

	printf("Stringi number: ");
	scanf("%d", &d);
	
	if(d==1) {
		*loend = (*loend)->next;
	}
	else {
		for(i=0; i<d-2; i++) {
			if(abi->next->next == NULL) {
				printf("Selline string puudub!\n");
				return;
			}
			abi = abi->next;
		}
		abii = abi;
		abi = abi->next;
		abii->next = abii->next->next;
	}

	free(abi->str);
	free(abi);

	return;
}

void findfromahel(struct ahel *loend) {
	int i;
	char *buffer;

	printf("Otsitav string: ");
	buffer = getstring();
	
	for(i=1; loend != NULL; i++) {
		if(strcmp(buffer, loend->str) == 0) {
			printf("Leitud positsioonilt %i.\n", i);
			return;
		}
		loend = loend->next;
	}

	printf("Stringi ei leidunud.\n");
	return;
}

char *getstring(void) {
	char input[81], *buffer;
	
	input[0] = ' ';
	input[1] = 0;
	buffer = malloc(1);
	*buffer = 0;
	
	while(input[strlen(input)-1] != '\n') {
		fgets(input, 81, stdin);
		buffer = realloc(buffer, strlen(buffer) + strlen(input) + 1);
		strcat(buffer, input);
	}

	return buffer;
}