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Given a unsigned int x, I want to set the nth bit to y, and y can be either 0 or 1. Is it possible to create an expression using bitwise operators to do this while avoiding the use of any conditional statements? Thanks.

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Please read How to ask. – segarci Feb 6 at 7:26
up vote 1 down vote accepted 
x = (x & (~(1 << n))) | (y << n)

Quite simple. (First, clear the nth bit, and set nth bit to 1 if y is 1.

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Still this has a condition, even if it is in one line. – Eun Feb 6 at 7:39
    
Thank you! I never considered doing it this way. – user95297 Feb 6 at 7:39
    
@Eun By condition I meant without having to check the value of y using an if-else statement or something similar. – user95297 Feb 6 at 7:40
up vote 0 down vote 
x ^= (-y ^ x) & (1 << n);
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This is not unconditional. OP wants this without any condition – Eun Feb 6 at 7:30
    
I am aware of this, but I am wondering if it is possible to incorporate y into the expression so that both cases (with y being 0 or 1) can be handled with one statement. – user95297 Feb 6 at 7:31
    
@Eun Sorry you're right, I missed that. Fixed my answer. – zenith Feb 6 at 7:41

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