uva 10294 polya定理

#include<cstdio>
typedef long long LL;
const int maxn = 100;
int gcd(int a, int b) {
  return b == 0 ? a : gcd(b, a%b);
}
int main() {
  int n, t;
  while(scanf("%d%d", &n, &t) == 2 && n) {
    LL pow[maxn];
    pow[0] = 1;
    for(int i = 1; i <= n; i++) pow[i] = pow[i-1] * t;
    LL a = 0;
    for(int i = 0; i < n; i++) a += pow[gcd(i, n)];
    LL b = 0;
    if(n % 2 == 1) b = n * pow[(n+1)/2];
    else b = n/2 * (pow[n/2+1] + pow[n/2]);
    printf("%lld %lld\n", a/n, (a+b)/2/n);
  }
  return 0;
}

书上的代码；