package java2;
public class mettl31 {
public static int output1;
public static void fn(int n) {
int c = 0;
int sum = 1;
for (int i = 3; i <=
n; i = i + 2) {
if (c == 0) {
sum
= sum + i;
c
= 1;
}
else if (c == 1) {
sum
= sum - i;
c
= 0;
}
}
output1 = sum;
}
public static void main(String[]
args) {
fn(9);
System.out.println(output1);
}
}