oj.uz

Submission #152805

# Submission time Handle Problem Language Result Execution time Memory
152805 2019-09-09T15:19:26 Z Mercenary Building Bridges (CEOI17_building) C++14
60 / 100
 187 ms 4660 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){
        while(m >= 1 && res[m - 1].x == c.x && res[m - 1].y > c.y)--m , res.pop_back();
        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(mid + 1 < s.size() &&
           s[mid].x * x + s[mid].y >= s[mid + 1].x * x + s[mid + 1].y)l = mid + 1;
        else h = mid - 1;
    }
    ll res = 1e18;
    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[build].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:53:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(mid + 1 < s.size() &&
            ~~~~~~~~^~~~~~~~~~
building.cpp:57:8: warning: unused variable 'res' [-Wunused-variable]
     ll res = 1e18;
        ^~~
building.cpp: In function 'int main()':
building.cpp:95:10: 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:96:10: 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

# 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 3 ms 376 KB Output is correct
5 Correct 3 ms 376 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 187 ms 2848 KB Output is correct
2 Correct 187 ms 2920 KB Output is correct
3 Correct 187 ms 3076 KB Output is correct
4 Correct 166 ms 3420 KB Output is correct
5 Correct 118 ms 4660 KB Output is correct

Subtask #3
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 3 ms 376 KB Output is correct
5 Correct 3 ms 376 KB Output is correct
6 Correct 187 ms 2848 KB Output is correct
7 Correct 187 ms 2920 KB Output is correct
8 Correct 187 ms 3076 KB Output is correct
9 Correct 166 ms 3420 KB Output is correct
10 Correct 118 ms 4660 KB Output is correct
11 Correct 168 ms 3640 KB Output is correct
12 Correct 186 ms 3668 KB Output is correct
13 Incorrect 89 ms 3448 KB Output isn't correct
14 Halted 0 ms 0 KB -