Problem:
Score : 200 points

Problem Statement

There are N children, numbered 1, 2, ..., N.

Snuke has decided to distribute x sweets among them.
He needs to give out all the x sweets, but some of the children may get zero sweets.

For each i (1 \leq i \leq N), Child i will be happy if he/she gets exactly a_i sweets.
Snuke is trying to maximize the number of happy children by optimally distributing the sweets.
Find the maximum possible number of happy children.

Constraints

All values in input are integers.

2 \leq N \leq 100

1 \leq x \leq 10^9

1 \leq a_i \leq 10^9

Input

Input is given from Standard Input in the following format:

N x
a_1 a_2 ... a_N

Output

Print the maximum possible number of happy children.

Sample Input 1

3 70
20 30 10

Sample Output 1

2

One optimal way to distribute sweets is (20, 30, 20).

Sample Input 2

3 10
20 30 10

Sample Output 2

1

The optimal way to distribute sweets is (0, 0, 10).

Sample Input 3

4 1111
1 10 100 1000

Sample Output 3

4

The optimal way to distribute sweets is (1, 10, 100, 1000).

Sample Input 4

2 10
20 20

Sample Output 4

0

No children will be happy, no matter how the sweets are distributed.

Solution in C (Clang 3.8.0) (judge verdict: Accepted)

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <ctype.h>
#include <stdint.h>
#include <string.h>
#include <wchar.h>

#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define ABS(a) ((a) < 0 ? -(a) : (a))
#define ABSS(a, b) ((a) > (b) ? (a) - (b) : (b) - (a))

int compare_f(const void *a, const void *b) {
	return *((size_t *)a) < *((size_t *)b) ? -1 : 1;
}

static size_t comb(const size_t n, const size_t r) {
	size_t result = 1;

	for (size_t i = 0; i < r; i++) {
		result *= n - i;
		result /= i + 1;
	}

	return result;
}

static bool sameStringExist(char W[100][11], const size_t N, const char *w)
{
	bool sameStringExist = false;
	for (size_t idx = 0; idx < N; idx++) {
		if (strcmp(W[idx], w) == 0) {
			sameStringExist = true;
			break;
		}
	}

	return sameStringExist;
}

int main(void) {
	size_t N, x, a[100];

	scanf("%zu %zu\n", &N, &x);
	for (size_t idx = 0; idx < N; idx++) {
		scanf("%zu", &a[idx]);
		if (idx < N - 1) {
			scanf(" ");
		}
	}

	qsort(a, N, sizeof(size_t), compare_f);

	size_t num = 0;
	size_t count = 0;
	for (size_t idx = 0; idx < N; idx++) {
		if (idx < N - 1) {
			if (num + a[idx] <= x) {
				num += a[idx];
				count++;
			}
		}
		else {
			if (num + a[idx] == x) {
				num += a[idx];
				count++;
			}
		}
	}


	printf("%zu\n", count);

	return 0;
}