oj.uz

Submission #77591

# Submission time Handle Problem Language Result Execution time Memory
77591 2018-09-28T19:06:21 Z duality Building Bridges (CEOI17_building) C++11
100 / 100
 334 ms 13316 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.size() >= 2) && 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 376 KB Output is correct
2 Correct 2 ms 468 KB Output is correct
3 Correct 2 ms 468 KB Output is correct
4 Correct 2 ms 540 KB Output is correct
5 Correct 3 ms 540 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 79 ms 2536 KB Output is correct
2 Correct 73 ms 2572 KB Output is correct
3 Correct 78 ms 2636 KB Output is correct
4 Correct 70 ms 3432 KB Output is correct
5 Correct 98 ms 5108 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 468 KB Output is correct
3 Correct 2 ms 468 KB Output is correct
4 Correct 2 ms 540 KB Output is correct
5 Correct 3 ms 540 KB Output is correct
6 Correct 79 ms 2536 KB Output is correct
7 Correct 73 ms 2572 KB Output is correct
8 Correct 78 ms 2636 KB Output is correct
9 Correct 70 ms 3432 KB Output is correct
10 Correct 98 ms 5108 KB Output is correct
11 Correct 77 ms 5656 KB Output is correct
12 Correct 75 ms 6800 KB Output is correct
13 Correct 65 ms 7856 KB Output is correct
14 Correct 78 ms 9140 KB Output is correct
15 Correct 334 ms 13316 KB Output is correct
16 Correct 99 ms 13316 KB Output is correct
17 Correct 63 ms 13316 KB Output is correct
18 Correct 52 ms 13316 KB Output is correct