Task

Test whether an integer is even or odd.

There is more than one way to solve this task:

 Use the even and odd predicates, if the language provides them.
 Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
 Divide i by 2. The remainder equals 0 iff i is even. The remainder equals +1 or -1 iff i is odd.
 Use modular congruences:
 i ≡ 0 (mod 2) iff i is even.
 i ≡ 1 (mod 2) iff i is odd.


fn test(n i64) {
    print('Testing integer $n')
 
    if n&1 == 0 {
        print(' even')
    }else{
        print('  odd')
    }
 
    if n%2 == 0 {
        println(' even')
    }else{
        println('  odd')
    }
}
 
fn main(){
    test(-2)
    test(-1)
    test(0)
    test(1)
    test(2)
}