oj.uz

답안 #152811

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
152811 2019-09-09T16:00:30 Z Mercenary Building Bridges (CEOI17_building) C++14
100 / 100
 188 ms 8276 KB 
#include<bits/stdc++.h>

using namespace std;
#define taskname "A"
#define pb	push_back
#define mp 	make_pair
#ifndef LOCAL
#define cerr if(0)cout
#endif

typedef long double ld;
typedef long long ll;
typedef pair<int,int> ii;
const int maxn = 1e5 + 5;
const int logn = 18;

struct point{
    ll x , y;
    point(){};
    point(ll x , ll y):x(x) , y(y){};
    point operator + (point other){
        return point(x + other.x , y + other.y);
    }
    point operator - (point other){
        return point(x - other.x , y - other.y);
    }
    ld operator % (point other){
        return (ld)x * other.y - (ld)y * other.x;
    }
    bool operator < (point other){
        if(x == other.x)return y < other.y;
        return x > other.x;
    }
};

void build(vector<point> & s){
    vector<point> res;
    sort(s.begin(),s.end());
    int m = 0;
    for(point c : s){
        if(m >= 1 && res[m - 1].x == c.x && res[m - 1].y < c.y)continue;
        if(m >= 2 && (res[m - 1] - res[m - 2]) % (res[m - 1] - c) <= 0)--m , res.pop_back();
        ++m;res.pb(c);
    }
    s = res;
}

ll ans(vector<point> & s , ll x){
    if(s.size() == 0)return (ll)1e18;
    int l = 0 , h = s.size() - 1;
    while(l < h){
        int mid = l + h >> 1;
        if(s[mid].x * x + s[mid].y >= s[mid + 1].x * x + s[mid + 1].y)l = mid + 1;
        else h = mid;
    }
    return s[l].x * x + s[l].y;
}

void debug(vector<point> &s , ll x , ll y){
    for(point c : s){
        cout <<  c.x << " " << c.y << " " << x << " " << c.x * x + c.y + y << endl;
    }
    cout << endl;
}

vector<point> s[logn];

void add(point x){
    int build = 0;
    for(int i = 0 ; i < logn ; ++i){
        if(s[i].size() == 0){
            build = i;
            break;
        }
    }
    s[0].pb(x);
    for(int i = 0 ; i < build ; ++i){
        for(point & c : s[i])s[i + 1].pb(c);
        ::build(s[i + 1]);
        s[i].clear();
    }
    ::build(s[build]);
}

int n;
int h[maxn];
ll w[maxn] , dp[maxn];

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n;
    for(int i = 1 ; i <= n ; ++i)cin >> h[i];
    for(int i = 1 ; i <= n ; ++i){
        cin >> w[i];
        w[i] += w[i - 1];
    }
    for(int i = 2 ; i <= n ; ++i){
        add(point(2 * h[i - 1] , (ll)h[i - 1] * h[i - 1] - w[i - 1] + dp[i - 1]));
        dp[i] = 1e18;
        for(int j = 0 ; j < logn ; ++j){
            dp[i] = min(dp[i] , ans(s[j] , -h[i]) + w[i - 1] + (ll)h[i] * h[i]);
//            if(i == 97){
//                debug(s[j] , -h[i] , + w[i - 1] + (ll)h[i] * h[i]);
//            }
//            if(i == 97){
//                cout << ans(s[j] , -h[i]) + w[i - 1] + (ll)h[i] * h[i] << endl;
//            }
        }
//        cout << dp[i] << endl;
    }
    cout << dp[n];
}

Compilation message

building.cpp: In function 'll ans(std::vector<point>&, ll)':
building.cpp:52:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
         int mid = l + h >> 1;
                   ~~^~~
building.cpp: In function 'int main()':
building.cpp:93:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
building.cpp:94:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 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 3 ms 376 KB Output is correct
5 Correct 3 ms 376 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 184 ms 2968 KB Output is correct
2 Correct 188 ms 3196 KB Output is correct
3 Correct 183 ms 3192 KB Output is correct
4 Correct 163 ms 2952 KB Output is correct
5 Correct 118 ms 4864 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 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 3 ms 376 KB Output is correct
5 Correct 3 ms 376 KB Output is correct
6 Correct 184 ms 2968 KB Output is correct
7 Correct 188 ms 3196 KB Output is correct
8 Correct 183 ms 3192 KB Output is correct
9 Correct 163 ms 2952 KB Output is correct
10 Correct 118 ms 4864 KB Output is correct
11 Correct 164 ms 2764 KB Output is correct
12 Correct 188 ms 3156 KB Output is correct
13 Correct 86 ms 2680 KB Output is correct
14 Correct 188 ms 3832 KB Output is correct
15 Correct 168 ms 8276 KB Output is correct
16 Correct 119 ms 5300 KB Output is correct
17 Correct 60 ms 3320 KB Output is correct
18 Correct 60 ms 3320 KB Output is correct