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// abs.go

// description: returns absolute value using binary operation

// time complexity: O(1)

// space complexity: O(1)

package binary

// Abs returns absolute value using binary operation

// Principle of operation:

// 1) Get the mask by right shift by the base

// 2) Base is the size of an integer variable in bits, for example, for int32 it will be 32, for int64 it will be 64

// 3) For negative numbers, above step sets mask as 1 1 1 1 1 1 1 1 and 0 0 0 0 0 0 0 0 for positive numbers.

// 4) Add the mask to the given number.

// 5) XOR of mask + n and mask gives the absolute value.

func Abs(base, n int) int {

m := n >> (base - 1)

return (n + m) ^ m

}