Submission #1103489

#	Time	Username	Problem	Language	Result	Execution time	Memory
1103489		hqminhuwu	Flooding Wall (BOI24_wall)	C++14	58 / 100	5067 ms	22860 KiB

Main

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair <ll,ll> pll;
typedef pair <int,int> pii;
typedef pair <int,pii> piii;

#define forr(_a,_b,_c) for(int _a = (_b); _a <= int (_c); ++_a)
#define ford(_a,_b,_c) for(int _a = (_b) + 1; _a --> int (_c);)
#define forf(_a,_b,_c) for(int _a = (_b); _a < int (_c); ++_a)
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define all(x) begin(x),end(x)
#define mask(i) (1LL << (i))
#define bit(x, i) (((x) >> (i)) & 1)
#define bp __builtin_popcountll
#define file "test"

template<class X, class Y>
    bool minz(X &x, const Y &y) {
        if (x > y) {
            x = y;
            return true;
        } return false;
    }
template<class X, class Y>
    bool maxz(X &x, const Y &y) {
        if (x < y) {
            x = y;
            return true;
        } return false;
    }

const int N = 5e5 + 5;
const ll oo = (ll) 1e16;
const ll mod = 1e9 + 7; // 998244353;

int n;
ll a[N], b[N], bl[N], br[N], al[N], ar[N], res, fa[N], fb[N], za[N], zb[N], pw[N];

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef kaguya
        freopen(file".inp", "r", stdin); freopen(file".out", "w", stdout);
    #endif

    cin >> n;

    forr (i, 1, n){
        cin >> a[i];
    }

    forr (i, 1, n){
        cin >> b[i];
    }

    pw[0] = 1;
    forr (i, 1, n){
        pw[i] = pw[i - 1] * 2 % mod;
    }

    forr (i, 1, n){
        al[i] = ar[i] = bl[i] = br[i] = 1;
        ll tmp = 1;

        forf (j, 1, i){
            tmp = tmp * 2 % mod;
            int cnt = (a[j] <= a[i]) + (b[j] <= a[i]);
            al[i] = al[i] * cnt % mod;
            cnt = (a[j] <= b[i]) + (b[j] <= b[i]);
            bl[i] = bl[i] * cnt % mod;
        }
        
        forr (j, i + 1, n){
            int cnt = (a[j] <= a[i]) + (b[j] <= a[i]);
            ar[i] = ar[i] * cnt % mod;
            cnt = (a[j] <= b[i]) + (b[j] <= b[i]);
            br[i] = br[i] * cnt % mod;
        }
    }

    forr (i, 1, n){
        ll way = 1, sum = 0;
        
        forr (j, i + 1, n){
            if (b[j] > a[i]){
                ll tmp = (a[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += al[i] * pw[n - j] % mod * tmp % mod) %= mod;
            } else if (b[j] == a[i]){
                ll tmp = (a[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += (pw[i - 1 + n - j] - (pw[i - 1] - al[i] + mod) * (pw[n - j] - br[j] + mod) % mod + mod) % mod * tmp % mod) %= mod;
            }
            if (a[j] > a[i]){
                ll tmp = (a[i] * (way) % mod * (j - i - 1) - sum + mod) % mod;
                (res += al[i] * pw[n - j] % mod * tmp % mod) %= mod;
            } else if (a[i] == a[j]){
                ll tmp = (a[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += (pw[i - 1 + n - j] - (pw[i - 1] - al[i] + mod) * (pw[n - j] - ar[j] + mod) % mod + mod) % mod * tmp % mod) %= mod;
            }
            if (a[j] < a[i] && b[j] < a[i]){
                sum = (sum * 2 + (a[j] + b[j]) * (way)) % mod;
                way = way * 2 % mod;
            } else if (a[j] < a[i]){
                sum = (sum + a[j] * (way)) % mod;
                way = way % mod;
            } else if (b[j] < a[i]){
                sum = (sum + b[j] * (way)) % mod;
                way = way % mod;
            } else {
                break;
            }
        }


        way = 1, sum = 0;
               
        forr (j, i + 1, n){
            if (b[j] > b[i]){
                ll tmp = (b[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += bl[i] * pw[n - j] % mod * tmp % mod) %= mod;
            } else if (b[j] == b[i]){
                ll tmp = (b[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += (pw[i - 1 + n - j] - (pw[i - 1] - bl[i] + mod) * (pw[n - j] - br[j] + mod) % mod + mod) % mod * tmp % mod) %= mod;
            }
            if (a[j] > b[i]){
                ll tmp = (b[i] * (way) % mod * (j - i - 1) - sum + mod) % mod;
                (res += bl[i] * pw[n - j] % mod * tmp % mod) %= mod;
            } else if (b[i] == a[j]){
                ll tmp = (b[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += (pw[i - 1 + n - j] - (pw[i - 1] - bl[i] + mod) * (pw[n - j] - ar[j] + mod) % mod + mod) % mod * tmp % mod) %= mod;
            }
            if (a[j] < b[i] && b[j] < b[i]){
                sum = (sum * 2 + (a[j] + b[j]) * (way)) % mod;
                way = way * 2 % mod;
            } else if (a[j] < b[i]){
                sum = (sum + a[j] * (way)) % mod;
                way = way % mod;
            } else if (b[j] < b[i]){
                sum = (sum + b[j] * (way)) % mod;
                way = way % mod;
            } else {
                break;
            }
        }

       // cout << res << "\n";
    }
    
    reverse(a + 1, a + 1 + n);
    reverse(b + 1, b + 1 + n);

    forr (i, 1, n){
        al[i] = ar[i] = bl[i] = br[i] = 1;

        forf (j, 1, i){
            int cnt = (a[j] <= a[i]) + (b[j] <= a[i]);
            al[i] = al[i] * cnt % mod;
            cnt = (a[j] <= b[i]) + (b[j] <= b[i]);
            bl[i] = bl[i] * cnt % mod;
        }
        
        forr (j, i + 1, n){
            ar[i] = ar[i] * 2 % mod;
            br[i] = br[i] * 2 % mod;
        }
    }

    forr (i, 1, n){
        ll way = 1, sum = 0;
        
        forr (j, i + 1, n){
            // if (i == 2){
            //     cout << way << " " << sum << " " << b[j] << "\n";
            // }
            if (b[j] > a[i]){
                ll tmp = (a[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += al[i] * ar[j] % mod * tmp % mod) %= mod;
            }
            if (a[j] > a[i]){
                ll tmp = (a[i] * (way) % mod * (j - i - 1) - sum + mod) % mod;
                (res += al[i] * ar[j] % mod * tmp % mod) %= mod;
            }
            if (a[j] < a[i] && b[j] < a[i]){
                sum = (sum * 2 + (a[j] + b[j]) * (way)) % mod;
                way = way * 2 % mod;
            } else if (a[j] < a[i]){
                sum = (sum + a[j] * (way)) % mod;
                way = way % mod;
            } else if (b[j] < a[i]){
                sum = (sum + b[j] * (way)) % mod;
                way = way % mod;
            } else {
                break;
            }
        }

        //cout << res << "\n";


        way = 1, sum = 0;
        forr (j, i + 1, n){
            if (b[j] > b[i]){
                ll tmp = (b[i] * way % mod * (j - i - 1)  - sum + mod) % mod;
                (res += bl[i] * br[j] % mod * tmp % mod) %= mod;
            }
            if (a[j] > b[i]){
                ll tmp = (b[i] * (way) % mod * (j - i - 1) - sum + mod) % mod;
                (res += bl[i] * br[j] % mod * tmp % mod) %= mod;
            }
            if (a[j] < b[i] && b[j] < b[i]){
                sum = (sum * 2 + (a[j] + b[j]) * (way)) % mod;
                way = way * 2 % mod;
            } else if (a[j] < b[i]){
                sum = (sum + a[j] * (way)) % mod;
                way = way % mod;
            } else if (b[j] < b[i]){
                sum = (sum + b[j] * (way)) % mod;
                way = way % mod;
            } else {
                break;
            }
        }

    }

    cout << res << "\n";

    return 0;
}
/*



*/

• Subtask 1: 8 / 8
• Subtask 2: 17 / 17
• Subtask 3: 19 / 19
• Subtask 4: 14 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 30