SPOJ Problem 9948:Will it ever stop

如题。。http://www.spoj.com/problems/WILLITST/

#include<cstdio>
long long n;
int main(){
    scanf("%lld",&n);
    while(n>1){
        if (n==3||n==6){printf("NIE\n");return 0;}
        if (n&1)n=(n+1)/2*3;else n>>=1;
    }
    printf("TAK\n");
}