一本通1636：【例 6】计算器

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int max_n = 1e6;
const int HashMod = 1e5;
struct Hash_Map {
    struct Line {
        int k, v, next;
    } e[max_n];
    int HashMap[HashMod], cnt;
    void init(void) {
        memset(HashMap, -1, sizeof(HashMap));
        cnt = 0;
    }
    void add(int k, int v, int hashkey) {
        e[cnt] = Line{k, v, HashMap[hashkey]};
        HashMap[hashkey] = cnt++;
    }
    void insert(int k, int v) {
        add(k, v, k % HashMod);
    }
    int find(int key) {
        for (int i = HashMap[key % HashMod]; i != -1; i = e[i].next)
            if (e[i].k == key)
                return e[i].v;

        return -1;
    }
} mp;
ll qpow(ll a, ll n, ll p) {
    a %= p;
    n %= (p - 1);
    ll ans = 1;

    while (n) {
        if (n & 1)
            ans = ans * a % p;

        a = a * a % p;
        n >>= 1;
    }

    return ans;
}
ll generator(ll p) {
    ll phi = p - 1, n = p - 1;
    vector<ll> v;

    for (ll i = 2; i * i <= n; i++)
        if (n % i == 0) {
            v.push_back(i);

            while (n % i == 0)
                n /= i;

            if (n == 1)
                break;
        }

    if (n != 1) {
        v.push_back(n);
    }

    for (ll res = 2; res <= p - 1; res++) { //[2,p-1]
        bool flag = true;

        for (ll i = 0; i < v.size(); i++)
            if (qpow(res, phi / v[i], p) == 1) {
                flag = false;
                break;
            }

        if (flag)
            return res;
    }

    return -1;
}
ll BSGS(ll a, ll b, ll p) {
    a %= p;
    b %= p;

    if (a == 0) {
        if (b == 0)
            return 1;
        else
            return -1;
    }

    if (b == 1)
        return 0;

    ll m = ceil(sqrt((double)p));
    mp.init();

    for (ll i = 0, ret = b; i <= m; i++) {
        mp.insert(ret, i);
        ret = ret * a % p;
    }

    ll t = qpow(a, m, p);

    for (ll i = 1, ret = t; i <= m; i++) {
        ll x = mp.find(ret);

        if (x != -1)
            return i * m - x;

        ret = ret * t % p;
    }

    return -1;
}
ll gcd(ll a, ll b) {
    return b == 0 ? a : gcd(b, a % b);
}
void exgcd(ll a, ll b, ll &x, ll &y) {
    if (!b) {
        x = 1;
        y = 0;
        return ;
    } else {
        exgcd(b, a % b, y, x);
        y -= (a / b) * x;
    }
}
ll residue(ll a, ll b, ll p) {
    a %= p;
    b %= p;

    if (a == 0) {
        if (b == 0)
            return 0;
        else
            return -1;
    }

    ll x, y;
    exgcd(a, p, x, y);
    x = (x % p + p) % p;
    x = x * b % p;
    return x;
}
int main(void) {
    int t, k;
    ll y, z, p;
    scanf("%d%d", &t, &k);

    while (t--) {
        scanf("%lld%lld%lld", &y, &z, &p);

        if (k == 1)
            printf("%lld\n", qpow(y, z, p));
        else if (k == 2) {
            ll ans = residue(y, z, p);

            if (ans == -1)
                printf("Orz, I cannot find x!\n");
            else
                printf("%lld\n", ans);
        } else if (k == 3) {
            ll ans = BSGS(y, z, p);

            if (ans == -1)
                printf("Orz, I cannot find x!\n");
            else
                printf("%lld\n", ans % (p - 1));
        }
    }
}