oj.uz

Submission #1095812

# Submission time Handle Problem Language Result Execution time Memory
1095812 2024-10-03T08:34:43 Z TVSown Building Bridges (CEOI17_building) C++17
100 / 100
 43 ms 9852 KB 
///*** Sown_Vipro ***///
/// ->GIAI BA QUOC GIA<- ///

#include<bits/stdc++.h>
using namespace std;
//#pragma GCC optimize ("O3")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("popcnt")
#define F first
#define S second
#define pb push_back
#define ll long long
#define pi pair<int, int>
#define pii pair<int, pair<int, int> >
#define inp(name) if(fopen(name, "r")) freopen(name, "r", stdin);
#define out(name) if(fopen(name, "w")) freopen(name, "w", stdout);
#define szz(s) int(s.size())
#define int long long
const int N = 1e6 + 5, MAX = 1e6, oo = 1e9 + 5, MOD = 1e9 + 7;
int n;
int h[N], w[N];
long long s[N], dp[N];
struct Line {
    mutable ll k, m, p;
    bool operator<(const Line& o) const { return k < o.k; }
    bool operator<(ll x) const { return p < x; }
};

struct LineContainer : multiset<Line, less<>> {
    // (for doubles, use inf = 1/.0, div(a,b) = a/b)
    static const ll inf = LLONG_MAX;
    ll div(ll a, ll b) { // floored division
        return a / b - ((a ^ b) < 0 && a % b); }
    bool isect(iterator x, iterator y) {
        if (y == end()) return x->p = inf, 0;
        if (x->k == y->k) x->p = x->m > y->m ? inf : -inf;
        else x->p = div(y->m - x->m, x->k - y->k);
        return x->p >= y->p;
    }
    void add(ll k, ll m) {
        auto z = insert({k, m, 0}), y = z++, x = y;
        while (isect(y, z)) z = erase(z);
        if (x != begin() && isect(--x, y)) isect(x, y = erase(y));
        while ((y = x) != begin() && (--x)->p >= y->p)
            isect(x, erase(y));
    }
    ll query(ll x) {
        assert(!empty());
        auto l = *lower_bound(x);
        return l.k * x + l.m;
    }
} hull;

void solve(){
    cin >> n;
    for(int i = 1; i <= n; ++i){
        cin >> h[i];
    }
    for(int i = 1; i <= n; ++i){
        cin >> w[i];
        s[i] = s[i - 1] + w[i];
    }
    for(int i = 2; i <= n; ++i) dp[i] = 1e18;
    hull.add(2 * h[1], -(dp[1] + h[1] * h[1] - s[1]));
    for(int i = 2; i <= n; ++i){
        dp[i] = -hull.query(h[i]) + h[i] * h[i] + s[i - 1];
        hull.add(2 * h[i], -(dp[i] + h[i] * h[i] - s[i]));
    }
    cout << dp[n];
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    inp("in.txt");
    int t = 1;
//    cin >> t;
    while(t--){
        solve();
    }
}

Compilation message

building.cpp: In function 'int main()':
building.cpp:15:47: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 | #define inp(name) if(fopen(name, "r")) freopen(name, "r", stdin);
      |                                        ~~~~~~~^~~~~~~~~~~~~~~~~~
building.cpp:75:5: note: in expansion of macro 'inp'
   75 |     inp("in.txt");
      |     ^~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 3672 KB Output is correct
2 Correct 33 ms 3676 KB Output is correct
3 Correct 28 ms 3676 KB Output is correct
4 Correct 26 ms 3416 KB Output is correct
5 Correct 23 ms 4700 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 29 ms 3672 KB Output is correct
7 Correct 33 ms 3676 KB Output is correct
8 Correct 28 ms 3676 KB Output is correct
9 Correct 26 ms 3416 KB Output is correct
10 Correct 23 ms 4700 KB Output is correct
11 Correct 27 ms 3420 KB Output is correct
12 Correct 27 ms 3672 KB Output is correct
13 Correct 23 ms 3420 KB Output is correct
14 Correct 29 ms 3676 KB Output is correct
15 Correct 43 ms 9852 KB Output is correct
16 Correct 23 ms 4800 KB Output is correct
17 Correct 14 ms 3472 KB Output is correct
18 Correct 18 ms 3520 KB Output is correct