ModPow

8 lines tested

content/number-theory/ModPow.h — Noam527, source: folklore

const ll mod = 1000000007; // faster if const

ll modpow(ll b, ll e) {
	ll ans = 1;
	for (; e; b = b * b % mod, e /= 2)
		if (e & 1) ans = ans * b % mod;
	return ans;
}