next_power_of_two.js

/*
  Computes the next power-of-two integer greater than or equal to `num` via binary searching the bits
*/
const nextPOT = (num) => {
	num = num | 0;
	if (num === 0) {
		return 0;	
	}
	let min = 0;
	let max = 64; // assume numbers in JS are no larger than 64 bits
	let mid = 0;
	while (true) {
		mid = (((min + max) / 2) + min ) | 0;
		if ( num >> mid > 1 ) {
			min = mid + 1;
		}
		else if (num >> mid < 1) {
			max = mid;
		}
		else {
			break;		
		}
	}
	let res = 1 << mid;
	return res << (res === num ? 0 : 1);
};