Description
Given A,B,C, You should quickly calculate the result of A^B mod C. (1<=A,C<=1000000000,1<=B<=10^1000000).
Input
There are multiply testcases. Each testcase, there is one line contains three integers A, B and C, separated by a single space.
Output
For each testcase, output an integer, denotes the result of A^B mod C.
降幂公式:
//计算欧拉函数O(sqrt(n))ll Phi(ll x){ ll i; ll re = x; for (i = 2; i * i <= x; i++) if (x % i == 0) { re /= i; re *= i - 1; while (x % i == 0) { x /= i; } } if (x ^ 1) { re /= x, re *= x - 1; } return re;}ll Quick_Power(ll x, ll y, ll p){ ll re = 1; while (y) { if (y & 1) { (re *= x) %= p; } (x *= x) %= p; y >>= 1; } return re;}int Solve(int p){ if (p == 1) { return 0; } int phi_p = Phi(p); return Quick_Power(2, Solve(phi_p) + phi_p, p);}int T, n, a, c;string b;int main(){ ios_base::sync_with_stdio(false); // freopen("data.txt","r",stdin); while (cin >> a >> b >> c) { int phi_c = Phi(c); ll sum = 0; for (int i = 0; i < b.size(); i++) { sum = (sum * 10 + b[i] - '0') % (phi_c); } cout << Quick_Power(a, sum + phi_c, c) << endl; }}