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

int validate(int low, int high);
int genRand(int limit);
int validatePick(int pick, int first, int second, int third, int fourth, int fifth, int sixth, int seventh);
void printNums(int n, int first, int second, int third, int fourth, int fifth, int sixth, int seventh);
double calcOdds(int n, int k);


int main () {

	int largest, low, high, rv, group, limit, n, k, pick, ret;
	int first, second, third, fourth, fifth, sixth, seventh;
	double derp;
	srand(time(NULL));

	printf ("LOTTERY GENERATOR\n");
	printf ("Enter the largest number in your LOTTERY:\n");
	printf ("Enter a value (between 39 and 59) : ");

	largest = validate(low, high);

	printf ("Enter the amount of numbers you MUST select in the LOTTERY:\n");
	printf ("Enter a value (between 3 and 7): ");

	group = validate2(low, high);

	printf ("Your random LOTTERY numbers are: ");

	limit = largest;

	first = second = third = 0;
	fourth = fifth = sixth = seventh = -1;
	first = genRand(limit);
	pick = genRand(limit);
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
	pick = genRand(limit);
	}
	second = pick;
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
		pick = genRand(limit);
		}
	third = pick;
	if(group > 3) {
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
		pick = genRand(limit);
		}}
	fourth = pick;
	if(group > 4) {
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
		pick = genRand(limit);
		}}
	fifth = pick;
	if(group > 5) {
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
		pick = genRand(limit);
		}}
	sixth = pick;
	if(group > 6) {
	while(validatePick(pick, first, second, third, fourth, fifth, sixth, seventh) == 0){
		pick = genRand(limit);
		}
	seventh = pick;
	}

	printf ("%d %d %d %d %d %d %d\n", first, second, third, fourth, fifth, sixth, seventh);

	n = group;

	printNums(n, first, second, third, fourth, fifth, sixth, seventh);

	k = group;
	n = largest;

	ret = validatePick(pick, first, second, third, fourth, fifth, sixth, seventh);

	printf ("\n%d\n", ret);

	derp = calcOdds(n, k);

	//printf ("%f", derp);


}


int validate(int low, int high) {
	low = 39;
	high = 59;
	int largest=0, counter=0;

	scanf ("%d", &largest);
	while (counter == 0) {
		if (largest >= low && largest <= high) {
			printf ("Thank You!\n");
			counter++;
			}
		else {
			printf ("***Error! You entered '%d' ... Value must be between 39 and 59 inclusive!***\n", largest);
			printf ("Enter a value (between 39 and 59) : ");
			scanf ("%d", &largest);
		}
	}

	return largest;
	}

int validate2 (int low, int high) {
	low = 3;
	high = 7;
	int group=0, counter=0;

	scanf ("%d", &group);
	while (counter == 0) {
		if (group >= 3 && group <= 7) {
			printf ("Thank You!\n");
			counter++;
			}
		else {
			printf ("***Error! You entered '%d' ... Value must be between 3 and 7 inclusive!***\n", group);
			printf ("Enter a value (between 3 and 7) : ");
			scanf ("%d", &group);
			}
		}

	return group;
}

int genRand(int limit) {
    int randomNum = rand();

	while (randomNum >= limit) {
		randomNum = rand();
	}
    return randomNum;
}

int validatePick(int pick, int first, int second, int third, int fourth, int fifth, int sixth, int seventh){
	if (pick == first && first != -1)
		return 0;
	else if (pick == second && second != -1)
		return 0;
	else if (pick == third && third != -1)
		return 0;
	else if (pick == fourth && fourth != -1)
		return 0;
	else if (pick == fifth && fifth != -1)
		return 0;
	else if (pick == sixth && sixth != -1)
		return 0;
	else if (pick == seventh && seventh != -1)
		return 0;
	else
		return 1;

}

void  printNums (int n, int first, int second, int third, int fourth, int fifth, int sixth, int seventh) {
		printf ("Numbers Generated: %d\n", n); 										//Delete after Testing
		printf ("%d, %d, %d", first, second, third);

		if (n == 4)
			printf (", %d\n", fourth);
		else if (n == 5)
			printf (", %d, %d\n", fourth, fifth);
		else if (n == 6)
			printf (", %d, %d, %d\n", fourth, fifth, sixth);
		else if (n == 7)
			printf (", %d, %d, %d, %d\n", fourth, fifth, sixth, seventh);

}

 //= n! / ((n-k)! * k!)
 //odds = fun1 / (fun2 * fun3)

double calcOdds (int n, int k) { //n = largest   k = set
	int i, nk;
	double odds, fun23, fun1 = 1, fun2 = 1, fun3 = 1;

	nk = n - k;

	printf ("n = %d\n", n);
	printf ("k = %d\n", k);
	printf ("nk = %d\n", nk);


	for (i = 1; i <= n; i++)
		fun1 = fun1 * i;
	for (i = 1; i <= nk; i++)
		fun2 = fun2 * i;
	for (i = 1; i <= k; i++)
		fun3 = fun3 * i;

	fun23 = fun2 * fun3;
	odds = fun1 / (fun2 * fun3);

	printf ("odds: %f", odds);

	return odds;

}