Bursting Out All The Crackers

On the occasion of diwali, chef bought some array of $N$ crackers($a_1, a_2, a_3, ….a_n$) consisting of non-negative integers. But they can be fired only by a special fuljhari ($sparkler$: a kind of firework) with a magic number $K$ on it. We define operation of “burst” with integer parameter $K (1 \leq K \leq N)$ as follows: * Choose $K$ distinct array indices $1 \leq i1 \lt i2 \lt …. \lt ik \l