oj.uz

Submission #77590

# Submission time Handle Problem Language Result Execution time Memory
77590 2018-09-28T19:05:18 Z duality Building Bridges (CEOI17_building) C++11
30 / 100
 88 ms 2656 KB 
#define DEBUG 0

#include <bits/stdc++.h>
using namespace std;

#if DEBUG
// basic debugging macros
int __i__,__j__;
#define printLine(l) for(__i__=0;__i__<l;__i__++){cout<<"-";}cout<<endl
#define printLine2(l,c) for(__i__=0;__i__<l;__i__++){cout<<c;}cout<<endl
#define printVar(n) cout<<#n<<": "<<n<<endl
#define printArr(a,l) cout<<#a<<": ";for(__i__=0;__i__<l;__i__++){cout<<a[__i__]<<" ";}cout<<endl
#define print2dArr(a,r,c) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<a[__i__][__j__]<<" ";}cout<<endl;}
#define print2dArr2(a,r,c,l) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<setw(l)<<setfill(' ')<<a[__i__][__j__]<<" ";}cout<<endl;}

// advanced debugging class
// debug 1,2,'A',"test";
class _Debug {
    public:
        template<typename T>
        _Debug& operator,(T val) {
            cout << val << endl;
            return *this;
        }
};
#define debug _Debug(),
#else
#define printLine(l)
#define printLine2(l,c)
#define printVar(n)
#define printArr(a,l)
#define print2dArr(a,r,c)
#define print2dArr2(a,r,c,l)
#define debug
#endif

// define
#define MAX_VAL 999999999
#define MAX_VAL_2 999999999999999999LL
#define EPS 1e-6
#define mp make_pair
#define pb push_back

// typedef
typedef unsigned int UI;
typedef long long int LLI;
typedef unsigned long long int ULLI;
typedef unsigned short int US;
typedef pair<int,int> pii;
typedef pair<LLI,LLI> plli;
typedef vector<int> vi;
typedef vector<LLI> vlli;
typedef vector<pii> vpii;
typedef vector<plli> vplli;

// ---------- END OF TEMPLATE ----------

int h[100000];
LLI w[100001],dp[100000];
struct line { LLI m,b; };
bool comp(line a,line b) {
    if (a.m == b.m) return a.b < b.b;
    else return a.m > b.m;
}
int bad(line a,line b,line c) {
    return (long double) (b.b-a.b)*(b.m-c.m) >= (long double) (b.b-c.b)*(b.m-a.m);
}
vector<line> v1,v2;
int main() {
    int i;
    int n;
    scanf("%d",&n);
    for (i = 0; i < n; i++) scanf("%d",&h[i]);
    for (i = 0; i < n; i++) scanf("%lld",&w[i+1]),w[i+1] += w[i];

    int j,s = sqrt(n)+EPS;
    v1.pb((line){-2*h[0],(LLI) h[0]*h[0]-w[1]});
    for (i = 1; i < n; i++) {
        int l = 0,r = v1.size()-1;
        while (l < r) {
            int m = (l+r) / 2;
            if (v1[m].m*h[i]+v1[m].b < v1[m+1].m*h[i]+v1[m+1].b) r = m;
            else l = m+1;
        }
        dp[i] = (LLI) h[i]*h[i]+w[i]+v1[l].m*h[i]+v1[l].b;
        for (j = 0; j < v2.size(); j++) dp[i] = min(dp[i],(LLI) h[i]*h[i]+w[i]+v2[j].m*h[i]+v2[j].b);
        v2.pb((line){-2*h[i],(LLI) h[i]*h[i]-w[i+1]+dp[i]});
        if (v2.size() > s) {
            vector<line> temp(v1.size()+v2.size());
            sort(v2.begin(),v2.end(),comp);
            merge(v1.begin(),v1.end(),v2.begin(),v2.end(),temp.begin(),comp);
            v1.clear(),v2.clear();
            for (j = 0; j < temp.size(); j++) {
                if (!v1.empty() && (temp[j].m == v1.back().m)) continue;
                while (!v1.empty() && bad(v1[v1.size()-2],v1.back(),temp[j])) v1.pop_back();
                v1.pb(temp[j]);
            }
        }
    }
    printf("%lld\n",dp[n-1]);

    return 0;
}

Compilation message

building.cpp: In function 'int main()':
building.cpp:86:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (j = 0; j < v2.size(); j++) dp[i] = min(dp[i],(LLI) h[i]*h[i]+w[i]+v2[j].m*h[i]+v2[j].b);
                     ~~^~~~~~~~~~~
building.cpp:88:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (v2.size() > s) {
             ~~~~~~~~~~^~~
building.cpp:93:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (j = 0; j < temp.size(); j++) {
                         ~~^~~~~~~~~~~~~
building.cpp:72:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
building.cpp:73:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (i = 0; i < n; i++) scanf("%d",&h[i]);
                             ~~~~~^~~~~~~~~~~~
building.cpp:74:50: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (i = 0; i < n; i++) scanf("%lld",&w[i+1]),w[i+1] += w[i];
                             ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Output is correct
2 Correct 2 ms 372 KB Output is correct
3 Correct 2 ms 408 KB Output is correct
4 Correct 2 ms 612 KB Output is correct
5 Correct 2 ms 612 KB Output is correct

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 74 ms 2528 KB Output is correct
2 Correct 88 ms 2604 KB Output is correct
3 Incorrect 75 ms 2656 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Output is correct
2 Correct 2 ms 372 KB Output is correct
3 Correct 2 ms 408 KB Output is correct
4 Correct 2 ms 612 KB Output is correct
5 Correct 2 ms 612 KB Output is correct
6 Correct 74 ms 2528 KB Output is correct
7 Correct 88 ms 2604 KB Output is correct
8 Incorrect 75 ms 2656 KB Output isn't correct
9 Halted 0 ms 0 KB -