oj.uz

Submission #781529

# Submission time Handle Problem Language Result Execution time Memory
781529 2023-07-13T07:41:22 Z guagua0407 Building Bridges (CEOI17_building) C++17
100 / 100
 52 ms 8268 KB 
//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

struct line{
    ll a=(ll)1e12,b=(ll)1e18;
    ll val(ll x){
        return a*x+b;
    }
};

const int mxn=1e5+5;
const int mxs=1e6+5;
int n;
ll pre[mxn];
ll h[mxn];
ll w[mxn];
ll dp[mxn];
line segtree[mxs*4];

ll query(int x,int l=0,int r=mxs,int v=1){
    if(l==r) return segtree[v].val(x);
    int mid=(l+r)/2;
    if(x<=mid){
        return min(segtree[v].val(x),query(x,l,mid,v*2));
    }
    return min(segtree[v].val(x),query(x,mid+1,r,v*2+1));
}

void update(line L,int l=0,int r=mxs,int v=1){
    if(l==r){
        if(L.val(l)<segtree[v].val(l)){
            segtree[v]=L;
        }
        return;
    }
    int mid=(l+r)/2;
    if(segtree[v].a>L.a){
        swap(segtree[v],L);
    }
    if(L.val(mid)<segtree[v].val(mid)){
        swap(segtree[v],L);
        update(L,mid+1,r,v*2+1);
    }
    else{
        update(L,l,mid,v*2);
    }
}

int main() {_
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>h[i];
    }
    for(int i=1;i<=n;i++){
        cin>>w[i];
        pre[i]=pre[i-1]+w[i];
    }
    line L={-2*h[1],dp[1]+h[1]*h[1]-pre[1]};
    update(L);
    for(int i=2;i<=n;i++){
        dp[i]=h[i]*h[i]+pre[i]-w[i]+query(h[i]);
        line L={-2*h[i],dp[i]+h[i]*h[i]-pre[i]};
        update(L);
    }
    cout<<dp[n];
    return 0;
}
//maybe its multiset not set
/*
6
3 8 7 1 6 6
0 -1 9 1 2 0
*/

Compilation message

building.cpp: In function 'void setIO(std::string)':
building.cpp:12:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
building.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 2 ms 340 KB Output is correct
4 Correct 2 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 38 ms 4860 KB Output is correct
2 Correct 42 ms 4916 KB Output is correct
3 Correct 42 ms 5052 KB Output is correct
4 Correct 33 ms 4684 KB Output is correct
5 Correct 30 ms 7628 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 2 ms 340 KB Output is correct
4 Correct 2 ms 468 KB Output is correct
5 Correct 1 ms 468 KB Output is correct
6 Correct 38 ms 4860 KB Output is correct
7 Correct 42 ms 4916 KB Output is correct
8 Correct 42 ms 5052 KB Output is correct
9 Correct 33 ms 4684 KB Output is correct
10 Correct 30 ms 7628 KB Output is correct
11 Correct 52 ms 8268 KB Output is correct
12 Correct 44 ms 7888 KB Output is correct
13 Correct 39 ms 5836 KB Output is correct
14 Correct 43 ms 8072 KB Output is correct
15 Correct 31 ms 7628 KB Output is correct
16 Correct 30 ms 7628 KB Output is correct
17 Correct 22 ms 4556 KB Output is correct
18 Correct 27 ms 4556 KB Output is correct