Given a number N, check if it is positive, negative or zero without using conditional statements.
Input : 30 Output : 30 is positive Input : -20 Output : -20 is negative Input: 0 Output: 0 is zero
The signed shift n>>31 converts every negative number into -1 and every other into 0.
When we do a -n>>31, if it is a positive number then it will return -1 as we are doing -n>>31 and the vice versa when we do for a negative number.
But when we do for 0 then n>>31 and -n>>31 both returns 0, so we get a formula:
1 + (n>>31) – (-n>>31)
..1) when n is negative :
..2) when n is positive:
..3) when n is 0:
So we know it returns 0 when it is a negative number, it returns 1 when it is zero, returns 2 when it is a positive number.
So to not use if statements we store at 0th index “negative”, 1st index “zero” and at 2nd index “positive”, and print according to it.
30 is positive -20 is negative 0 is zero
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Improved By : jit_t