Week 0 ~ haysale.X

Farmer Ran suffered a terrible loss when giant Australian cockroaches
ate the entirety of his hay inventory, leaving him with nothing to
feed the cows. He hitched up his wagon with capacity C (1 <= C <=
50,000) cubic units and sauntered over to Farmer Don's to get some
hay before the cows miss a meal.

Farmer Don had a wide variety of H (1 <= H <= 5,000) hay bales for
sale, each with its own volume (1 <= V_i <= C). Bales of hay, you
know, are somewhat flexible and can be jammed into the oddest of
spaces in a wagon.

FR carefully evaluates the volumes so that he can figure out the
largest amount of hay he can purchase for his cows.

Given the volume constraint and a list of bales to buy, what is the
greatest volume of hay FJ can purchase?  He can't purchase partial
bales, of course. Each input line (after the first) lists a single
bale FJ can buy.

PROBLEM NAME: haysale.X

INPUT FORMAT:

* Line 1: Two space-separated integers: C and H

* Lines 2..H+1: Each line describes the volume of a single bale: V_i


SAMPLE INPUT:

7 3
2
6
5


INPUT DETAILS:

The wagon holds 7 volumetric units; three bales are offered for sale with
volumes of 2, 6, and 5 units, respectively.


OUTPUT FORMAT:

* Line 1: A single integer which is the greatest volume of hay FJ can
        purchase given the list of bales for sale and constraints.


SAMPLE OUTPUT:

7

OUTPUT DETAILS:

Buying the two smaller bales fills the wagon.