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#include <cstring> #include <cstdlib> #include <cassert> #include <cctype> #include <cmath> #include <algorithm> #include <functional> #include <utility> #include <vector> #include <map> #include <tr1/unordered_map> typedef long long ll; ll (ll a, ll b) { if(!b) { return a; } else { return gcd(b, a % b); } } void exgcd(ll a, ll b, ll &d, ll &x, ll &y) { if(!b) { d = a; x = 1; y = 0; } else { ll nx, ny; exgcd(b, a % b, d, nx, ny); x = ny; y = nx - ny * (a / b); } } ll inv(ll v, ll p) { ll d, x, y; exgcd(v, p, d, x, y); return (x + p) % p; } ll pow_mod(ll a, ll b, ll p) { ll ans = 1, res = a; while(b) { if(1LL & b) ans = ans * res % p; res = res * res % p; b >>= 1; } return ans; }
void desc(ll x, std::vector<int> &V) { ll bd = floor(sqrt((double)x) + 0.5); for(ll i = 2; i <= bd; i ++) { if(x % i == 0LL) { V.push_back(i); while(x % i == 0LL) x /= i; } } if(x > 1LL) V.push_back(int(x)); } ll find_g(ll p, ll phi, std::vector<int> &V) { if(p == 2LL) return 1; for(ll i = 2; i < p; i ++) { bool ok = true; for(int j = 0; j < V.size(); j ++) { ll c = phi / (ll)V[j]; if(pow_mod(i, c, p) == 1LL) { ok = false; break; } } if(ok) return i; } return -1LL; } ll bsgs(ll a, ll b, ll p) { if(a == 0LL) { return (b == 0LL) ? 1LL : -1LL; } int bd = ceil(sqrt((double)p)); std::tr1::unordered_map<ll, ll> ma; ll blk = 1LL; for(int i = 0; i < bd; i ++) { if(!ma.count(blk)) ma[blk] = i; blk = blk * a % p; } ll bs = 1LL; blk = inv(blk, p); for(int i = 0; (ll)i * (ll)bd < p; i ++) { ll th = b * bs % p; if(ma.count(th)) return ma[th] + i * bd; bs = bs * blk % p; } assert(false); return -1; }
ll equation(ll a, ll b, ll p) { ll ret = gcd(a, p); if(b % ret != 0LL) return 0; else return ret; } ll solve(ll a, ll b, ll mod, ll p, ll c) { if(b == 0LL) { ll ret = ceil((double(c)) / (double(a))); return pow_mod(p, c - ret, 2000000007LL); } else { if(b % p == 0LL) { ll nc = 0; while(b % p == 0LL) nc ++, b /= p, mod /= p; if(nc % a != 0LL) return 0LL; ll t = nc / a; return solve(a, b, mod, p, c - nc) * pow_mod(p, (a - 1LL) * t, 2000000007LL); } else { ll phi = mod / p * (p - 1LL); std::vector<int> d_phi; desc(phi, d_phi); ll g = find_g(mod, phi, d_phi); return equation(a, bsgs(g, b, mod), phi); } } }
int main() { int T; scanf("%d", &T); while(T --) { int a, b, k; scanf("%d%d%d", &a, &b, &k); k = 2 * k + 1; int bd = floor(sqrt((double)k) + 0.5); int ans = 1; for(int i = 2; i <= bd; i ++) { if(k % i == 0) { int c = 0, mod = 1; while(k % i == 0) k /= i, c ++, mod *= i; ans *= solve(a, b % mod, mod, i, c); } } if(k > 1) ans *= solve(a, b % k, k, k, 1); printf("%dn", ans); } return 0; }
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