Submission #48423

# Submission time Handle Problem Language Result Execution time Memory
48423 2018-05-13T02:45:16 Z wzy Building Bridges (CEOI17_building) C++11
100 / 100
178 ms 9188 KB
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
long long w[100005] , h[100005];
long long n;
long long dp[100005];
struct line{
    int x , y;
    line(int x , int y){
        this->x = x , this->y = y;
    }
};

bool operator <(line a , line b){
    if(a.x == b.x) return a.y > b.y;
    else return a.x > b.x;
}
template <class type> 
class CHT{
    public : 
    bool cmp(type a , type b , type c){
        return ((double)((double) (c.y) - (a.y)) * ((double) (a.x) - (b.x))   <= ((double) ((double) (a.x) - (c.x)) * ((double) (b.y) - (a.y)) ) )  ; 
    }
    int sizex(){
        return cht.size();
    }
    void addLINE(type a){
            while(cht.size() >= 2 && cmp(cht[cht.size() - 2] , cht[cht.size() - 1] , a)){
                cht.pop_back();
            }
        cht.push_back(a);
    }
    int eval(type b , int a){
        int w = (b.x) * a + (b.y);
        return w;
    }
    void mergev(vector<type> nhcht){
        vector<type> newcht;
        for(int i = 0 ; i < nhcht.size() + cht.size() ; i++) newcht.pb(line(0,0));
        std::merge(nhcht.begin() , nhcht.end() , cht.begin() , cht.end() , newcht.begin() );
        cht.clear();
        for(int i = 0 ; i < newcht.size() ; i++) addLINE(newcht[i]);
    }
    int querymin(int x){
        if(cht.size() == 0) return (int) 1e18;
        int l = 0 , r = cht.size() - 1;
        r--;
        int ansj = -1;
        while(l<=r){
            int mid = (l+r)/2;
            if(eval(cht[mid] , x) >= eval(cht[mid + 1] , x)){
                l = mid + 1;
                ansj = mid;
            }
            else r = mid - 1;
        }
        int bestvalue = eval(cht.front() , x);
        if(ansj != -1) bestvalue = min(bestvalue , eval(cht[ansj] , x));
        ansj ++;
        if(ansj < cht.size()) bestvalue = min(bestvalue , eval(cht[ansj] , x));

        return bestvalue;
    }
    vector<type> vectorT(){
        return cht;
    }
    void clearv(){
        cht.clear();
    }
    int querymax(int x){
        if(cht.size() == 0) return -(int) 1e18;
        int l = 0 , r = cht.size() - 1;
        r--;
        int ansj = -1;
        while(l<=r){
            int mid = (l+r)/2;
            if(eval(cht[mid] , x) <= eval(cht[mid+1],x)){
                l = mid + 1;
                ansj = mid;
            }
            else r = mid - 1;
        }
        int bestvalue = eval(cht.front() , x);
        if(ansj != -1) bestvalue = max(bestvalue , eval(cht[ansj] , x));
        ansj++;
        if(ansj < cht.size()) bestvalue = max(bestvalue ,eval(cht[ansj] , x));
        return bestvalue;
    }
   // private :
    // adicionar merge e checksize para fazer binary partition 
    vector<type> cht;
}; 

CHT <line> chts[33];

void addline(line a){
    vector<line> v;
    v.push_back(a);
    chts[0].mergev(v);
    for(int i = 0 ; i < 32 ; i++){
        int z = (1LL<<i);
        if(chts[i].sizex() > z){
            chts[i+1].mergev(chts[i].vectorT());
            chts[i].clearv();
        }
    }
    return ;
}


long long query(int x){

	long long bestvalue = (long long) 1e18;
	for(int i = 0 ; i < 32 ; i++){
        bestvalue  = min(bestvalue , chts[i].querymin(x));
    }
    return bestvalue;
}


int32_t main(){
	scanf("%lld" , &n);
	dp[0] = 0;
	for(int i = 1 ; i <=n ;i ++){
		scanf("%lld" , &h[i]);
	}
	w[0] = 0;
	for(int i = 1 ; i <=n ;i ++){
		scanf("%lld" , &w[i]);
		w[i] += w[i-1];
	}
	dp[1] = 0;
	addline(line(-2*h[1] , h[1]*h[1]  - w[1] ));
	for(int i = 2 ; i <= n ;i ++){
		dp[i] = query(h[i]) + h[i]*h[i] + w[i-1];
		addline(line(-2*h[i] , h[i]*h[i] - w[i] + dp[i]));
	}
	printf("%lld\n" , dp[n]);
}

Compilation message

building.cpp: In instantiation of 'void CHT<type>::mergev(std::vector<_Tp>) [with type = line]':
building.cpp:100:21:   required from here
building.cpp:40:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i = 0 ; i < nhcht.size() + cht.size() ; i++) newcht.pb(line(0,0));
building.cpp:43:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i = 0 ; i < newcht.size() ; i++) addLINE(newcht[i]);
building.cpp: In instantiation of 'long long int CHT<type>::querymin(long long int) [with type = line]':
building.cpp:116:56:   required from here
building.cpp:61:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(ansj < cht.size()) bestvalue = min(bestvalue , eval(cht[ansj] , x));
building.cpp: In function 'int32_t main()':
building.cpp:123:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld" , &n);
  ~~~~~^~~~~~~~~~~~~
building.cpp:126:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld" , &h[i]);
   ~~~~~^~~~~~~~~~~~~~~~
building.cpp:130:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld" , &w[i]);
   ~~~~~^~~~~~~~~~~~~~~~
# 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 428 KB Output is correct
4 Correct 4 ms 428 KB Output is correct
5 Correct 3 ms 480 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 153 ms 3044 KB Output is correct
2 Correct 145 ms 3080 KB Output is correct
3 Correct 178 ms 3284 KB Output is correct
4 Correct 178 ms 3284 KB Output is correct
5 Correct 120 ms 5780 KB Output is correct
# 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 428 KB Output is correct
4 Correct 4 ms 428 KB Output is correct
5 Correct 3 ms 480 KB Output is correct
6 Correct 153 ms 3044 KB Output is correct
7 Correct 145 ms 3080 KB Output is correct
8 Correct 178 ms 3284 KB Output is correct
9 Correct 178 ms 3284 KB Output is correct
10 Correct 120 ms 5780 KB Output is correct
11 Correct 136 ms 5780 KB Output is correct
12 Correct 160 ms 5780 KB Output is correct
13 Correct 110 ms 5780 KB Output is correct
14 Correct 147 ms 5780 KB Output is correct
15 Correct 137 ms 9188 KB Output is correct
16 Correct 115 ms 9188 KB Output is correct
17 Correct 71 ms 9188 KB Output is correct
18 Correct 65 ms 9188 KB Output is correct