if(n % 2 == 0){
for(int i = n; i >= 0; i-=2){
System.out.println(i);
}
}
else{
for(int i = n - 1; i >= 0; i-=2){
System.out.println(i);
}
}
Output when n = 12
12
10
8
6
4
2
0
Output when n = 21
20
18
16
14
12
10
8
6
4
2
0
The above code is written in Java.
The if block checks if n is even by finding the modulus/remainder of n with 2. If the remainder is 0, then n is even. If n is even, then the for loop starts at i = n. At each cycle of the loop, the value of i is reduced by 2 and the value is outputted to the console.
If n is odd, then the else block is executed. In this case, the for loop starts at i = n - 1 which is the next lower even number. At each cycle of the loop, the value of i is reduced by 2 and the value is outputted to the console.
Sample outputs for given values of n have been provided above.
