oj.uz

Submission #133217

# Submission time Handle Problem Language Result Execution time Memory
133217 2019-07-20T09:26:08 Z lyc Building Bridges (CEOI17_building) C++14
100 / 100
 144 ms 12536 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef pair<ii, int> ri3;
#define mp make_pair
#define pb push_back
#define fi first
#define sc second
#define SZ(x) (int)(x).size()
#define ALL(x) begin(x), end(x) 
#define REP(i, n) for (int i = 0; i < n; ++i) 
#define FOR(i, a, b) for (int i = a; i <= b; ++i)
#define RFOR(i, a, b) for (int i = a; i >= b; --i)

const int MAXN = 1e5+5;

int N;
int H[MAXN];
ll W[MAXN];

const ll is_query = -(1LL<62);

struct Line {
    ll m, b;
    mutable function<const Line*()> succ;
    bool operator<(const Line& rhs) const {
        if (rhs.b != is_query) return m > rhs.m;
        const Line* s = succ();
        if (!s) return 0;
        ll x = rhs.m;
        return b - s->b >= (s->m - m) * x;
    }
};

struct HullDynamic : public multiset<Line> {
    bool bad(iterator y) {
        auto z = next(y);
        if (y == begin()) {
            if (z == end()) return 0;
            return y->m == z->m and y->b > z->b;
        }
        auto x = prev(y);
        if (z == end()) return y->m == x->m and y->b > x->b;
        return (y->b - z->b) * (y->m - x->m) <= (x->b - y->b) * (z->m - y->m);
    }

    void add(Line l) {
        auto y = insert(l);
        y->succ = [=] { return next(y) == end() ? 0 : &*next(y); };
        if (bad(y)) { erase(y); return; }
        while (y != begin() and bad(prev(y))) erase(prev(y));
        while (next(y) != end() and bad(next(y))) erase(next(y));
    }

    ll query(ll x) {
        auto l = *lower_bound({ x, is_query });
        return l.m * x + l.b;
    }
} ch;

int main() {
    //freopen("in.txt", "r", stdin);
    ios::sync_with_stdio(false);
    cin.tie(0);

    cin >> N;
    FOR(i,1,N){ cin >> H[i]; }
    W[0] = 0;
    FOR(i,1,N){ cin >> W[i]; W[i] += W[i-1]; }

    //res[i] = res[j] + W[j-1]-W[i] + H[i]*H[i] - 2*H[i]*H[j] + H[j]*H[j];
    //res[i] = -W[i]+H[i]*H[i] -2*H[i]*H[j] + H[j]*H[j] + res[j] + W[j-1];
    ll res[N+1];
    res[N] = 0; ch.add({-2LL*H[N], (ll)H[N]*H[N] + res[N] + W[N-1]});
    RFOR(i,N-1,1){
        res[i] = (ll)-W[i]+(ll)H[i]*H[i] + ch.query(H[i]);
        ch.add({-2LL*H[i], (ll)H[i]*H[i] + res[i] + W[i-1]});
    }

    cout << res[1] << '\n';
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 79 ms 3428 KB Output is correct
2 Correct 79 ms 3448 KB Output is correct
3 Correct 80 ms 3392 KB Output is correct
4 Correct 72 ms 3192 KB Output is correct
5 Correct 71 ms 5112 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 79 ms 3428 KB Output is correct
7 Correct 79 ms 3448 KB Output is correct
8 Correct 80 ms 3392 KB Output is correct
9 Correct 72 ms 3192 KB Output is correct
10 Correct 71 ms 5112 KB Output is correct
11 Correct 72 ms 3608 KB Output is correct
12 Correct 80 ms 3424 KB Output is correct
13 Correct 50 ms 3448 KB Output is correct
14 Correct 77 ms 3576 KB Output is correct
15 Correct 144 ms 12536 KB Output is correct
16 Correct 73 ms 5068 KB Output is correct
17 Correct 32 ms 3320 KB Output is correct
18 Correct 32 ms 3400 KB Output is correct