Submission #1187643

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187643		Aviansh	Hexagonal Territory (APIO21_hexagon)	C++20	9 / 100	0 ms	328 KiB

hexagon

#include "hexagon.h"

#include <bits/stdc++.h>

using namespace std;

const int mod = 1e9+7;

long long modinv(long long x){
    int need  = mod-2;
    long long ans = 1;
    long long curr = x;
    for(int i = 0;i<32;i++){
        if((1<<i)&need){
            ans*=curr;
            ans%=mod;
        }
        curr*=curr;
        curr%=mod;
    }
    return ans;
}

int draw_territory(int n, int a, int b,vector<int> d, vector<int> l) {
    assert(n==3);
    assert(l[0]==l[1]&&l[1]==l[2]);
    int s = l[0]+1;
    long long ans = 1LL*s*(s+1);
    ans/=2;
    ans%=mod;
    ans*=a;
    ans%=mod;
    s--;
    long long bsum = (1LL*s*(s+1))/2;
    bsum%=mod;
    bsum+=(((((1LL*s*(s+1))%mod)*(2*s+1))%mod)*modinv(6))%mod;
    bsum%=mod;
    bsum*=b;
    bsum%=mod;
    ans+=bsum;
    ans%=mod;
    return ans;
}

• Subtask 1: 3 / 3
• Subtask 2: 6 / 6
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 15
• Subtask 6: 0 / 19
• Subtask 7: 0 / 18
• Subtask 8: 0 / 16