# HDOJ 2053 Switch Game

Problem Description
There are many lamps in a line. All of them are off at first. A series of operations are carried out on these lamps. On the i-th operation, the lamps whose numbers are the multiple of i change the condition ( on to off and off to on ).

Input
Each test case contains only a number n ( 0< n < = 10^5) in a line.

Output
Output the condition of the n-th lamp after infinity operations ( 0 - off, 1 - on ).

Sample Input
1
5

Sample Output
1
0

Hinthint

Consider the second test case:

```The initial condition      : 0 0 0 0 0 …
After the first operation  : 1 1 1 1 1 …
After the second operation : 1 0 1 0 1 …
After the third operation  : 1 0 0 0 1 …
After the fourth operation : 1 0 0 1 1 …
After the fifth operation  : 1 0 0 1 0 …
```

The later operations cannot change the condition of the fifth lamp any more. So the answer is 0.

```import java.util.Scanner;

public class Main {
//  static boolean[] islight = new boolean[100002];

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNext()) {
int n = sc.nextInt();

//          for(int i=1;i>=n;i++){
//              islight[i] = false;
//          }
//
//          for (int i = 1; i >= n; i++) {
//              for (int j = 1; j >= n; j++) {
//                  if(j%i==0){
//                      islight[j] = !islight[j];
//                  }
//              }
//          }
//
//          if(islight[n]){
//              System.out.println("1");
//          }else{
//              System.out.println("0");
//          }
//          超时

int k =0;
for(int i=1;i>=n;i++){
if(n%i==0){
k++;
}
}

if(k%2==0){
System.out.println("0");
}else{
System.out.println("1");
}

}

}
}

```
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