欧拉降幂公式 Super A^B mod C

时间:2021-08-16 10:57:26

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:欧拉降幂公式 Super A^B mod C
//计算欧拉函数O(sqrt(n))
ll Phi(ll x)
{
ll i;
ll re = x;
for (i = ; i * i <= x; i++)
if (x % i == )
{
re /= i;
re *= i - ;
while (x % i == )
{
x /= i;
}
}
if (x ^ )
{
re /= x, re *= x - ;
}
return re;
}
ll Quick_Power(ll x, ll y, ll p)
{
ll re = ;
while (y)
{
if (y & )
{
(re *= x) %= p;
}
(x *= x) %= p;
y >>= ;
}
return re;
}
int Solve(int p)
{
if (p == )
{
return ;
}
int phi_p = Phi(p);
return Quick_Power(, 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 = ;
for (int i = ; i < b.size(); i++)
{
sum = (sum * + b[i] - '') % (phi_c);
}
cout << Quick_Power(a, sum + phi_c, c) << endl;
}
}