Submission #1073596

#	Time	Username	Problem	Language	Result	Execution time	Memory
1073596		coolboy19521	Energetic turtle (IZhO11_turtle)	C++17	100 / 100	19 ms	1680 KiB

turtle

// Thanks Benq
 
#include "bits/stdc++.h"
#define ll long long
#define int ll
 
using namespace std;
 
const int sz = 6e5 + 1;
const int sm = 25;
 
vector<pair<int,int>> vp;
vector<int> ps;
ll wz[sm][sm];
ll dp[sm][sm];
bool sv[sz];
 
ll bpw(ll x, ll b, ll z) {
    ll r = 1;
    while (b) {
        if (b & 1)
            (r *= x) %= z;
        (x *= x) %= z;
        b >>= 1;
    }
    return r;
}
 
ll nck(ll n, ll k, ll z) {
    if (n < k || n < 0) return 0;
    if (k == 0 || n == k) return 1;
	if (k == 1 || k == n - 1) return n;
    ll r = 1;
    k = min(k, n - k);
    for (ll p : ps) {
        if (p > n) break;
        int e = 0;
        for (ll c = p; c <= n; c *= p) {
            if (c <= k) e -= k / c;
            if (c <= n - k) e -= (n - k) / c;
            e += n / c;
        }
        (r *= bpw(p, e, z)) %= z;
    }
    return r;
}
 
ll gt(pair<int,int>& f, pair<int,int>& s, int z) {
    int xds = s.first - f.first;
    int yds = s.second - f.second;
    return nck(xds + yds, yds, z);
}
 
ll sb(ll a, ll b, ll z) {
    return (a + z - b) % z;
}
 
ll ml(ll a, ll b, ll z) {
    return a * b % z;
}
 
ll ad(ll a, ll b, ll z) {
    return (a + b) % z;
}
 
signed main() {
    ll n, m, k, t, z;
    cin >> n >> m >> k >> t >> z;
    int sd = n + m + 2;
 
    for (ll i = 2; i < sd; i ++) {
        if (sv[i]) continue;
        ps.push_back(i);
        sv[i] = true;
        for (ll j = i * i; j < sd; j += i)
            sv[j] = true;
    }
 
    for (int i = 0; i < k; i ++) {
        int x, y;
        cin >> x >> y;
        vp.push_back(make_pair(x, y));
    }

    vp.push_back(make_pair(0, 0));
    vp.push_back(make_pair(n, m));
 
    sort(begin(vp), end(vp));
    k = vp.size();
 
    for (int i = 1; i < k; i ++) {
        vector<int> an(k + 2);
        for (int j = i - 1; 0 <= j; j --) {
            if (vp[j].first > vp[i].first || vp[j].second > vp[i].second) continue;
            wz[j][i] = an[j] = gt(vp[j], vp[i], z);
            for (int l = j + 1; l < i; l ++)
                wz[j][i] = sb(wz[j][i], ml(wz[j][l], an[l], z), z);
        }
    }

    dp[0][1] = 1;
 
    for (int i = 1; i < k; i ++)
        for (int j = 0; j < i; j ++)
            for (int l = 2; l <= min(i + 1, t + 2); l ++)
                dp[i][l] = ad(dp[i][l], ml(dp[j][l - 1], wz[j][i], z), z);
 
    ll r = 0;
 
    for (int i = 1; i <= t + 2; i ++)
        r = ad(r, dp[k - 1][i], z);
 
    cout << r << '\n';
}

• Subtask 1: 100 / 100