oj.uz

Submission #971064

# Submission time Handle Problem Language Result Execution time Memory
971064 2024-04-27T21:48:19 Z _rain_ Split the sequence (APIO14_sequence) C++14
0 / 100
 25 ms 13068 KB 
/** author : _RAIN_ **/
#include<bits/stdc++.h>
using namespace std;
 
using i64 = long long;
using ui64 = unsigned long long;
 
#define MASK(x) ((i64)(1) << (x))
#define BIT(mask , x) (((mask) >> (x)) & (1))
 
template<class T>
    bool maximize(T &a , T b) {if (a < b) return a = b , true; else return false;}
template<class T>
    bool minimize(T &a , T b) {if (a > b) return a = b , true; else return false;}
template<class T>
    T gcd(T x , T y) {while (y) swap(y , x %= y); return x;}
template<class T>
    T lcm(T x , T y) {return (x * y) / gcd(x , y);}
#define sz(x) (int)((x).size())
struct Line
{
    i64 a , b;
    Line(i64 a , i64 b) : a(a) , b(b) {};
};
struct Hull
{
    Line X;
    double intersec;
    int idx;
};
class Convex_hull
{
    public:
        vector<Hull> line;
        double getintersec(Line x , Line y)
        {
            return (double)(y.b - x.b) / (x.a - y.a);
        }
        i64 getval(Line a , i64 x)
        {
            return a.a * x + a.b;
        }
        void addline(Line a , int idx)
        {
            int n = sz(line);
            while (n > 1 && getintersec(line[n - 2].X , a) <= getintersec(line[n - 1].X , line[n - 2].X))
                line.pop_back() , --n;
            if (!sz(line))
                line.push_back({a , LLONG_MIN , idx});
            else line.push_back({a , getintersec(a , line[n - 1].X), idx});
            return;
        }
        pair<i64 , int> find(i64 val)
        {
            int low = 0 , high = sz(line) - 1 , p = 0;
            while (low <= high)
            {
                int mid = low + high >> 1;
                if (line[mid].intersec <= val) p = mid , low = mid + 1;
                    else high = mid - 1;
            }
            return {getval(line[p].X , val) , line[p].idx};
        }
        void add(i64 a , i64 b , int idx)
        {
            addline(Line{a , b} , idx);
            return;
        }
};
 
const int maxn = 1e5;
const int maxk = 200;
i64 dp[maxn + 2] , g[maxn + 2] , a[maxn + 2] , pre[maxn + 2];
int trace[maxk + 2][maxn + 2];
int n , k;
 
void solve(int idx)
{
    Convex_hull bag1;
    for (int i = 1; i <= n; ++i) dp[i] = LLONG_MAX;
    for (int i = 1; i <= n; ++i)
    {
        if (bag1.line.size())
        {
            pair<i64 , int> val = bag1.find(pre[i - 1]);
            dp[i] = val.first - pre[n] * pre[i - 1] + pre[i - 1] * pre[i - 1];
            trace[idx][i] = val.second;
        }
        if (g[i] != LLONG_MAX)
            bag1.add(-pre[i - 1] , pre[n] * pre[i - 1] + g[i] , i);
    }
    for (int i = 1; i <= n; ++i) g[i] = dp[i];
}
 
int32_t main(void)
{
    cin.tie(nullptr)->sync_with_stdio(false);
    const string name = "main";
    if (fopen((name + ".inp").c_str() , "r"))
    {
        (void)!freopen((name + ".inp").c_str() , "r" , stdin);
        (void)!freopen((name + ".out").c_str() , "w+", stdout);
    }
    cin >> n >> k; ++k;
    memset(pre , 0 , sizeof pre);
    for (int i = 1; i <= n; ++i) cin >> a[i];
    for (int i = 1; i <= n; ++i) pre[i] = pre[i - 1] + a[i];
    memset(dp , 0x3f , sizeof dp);
    memset(g , 0x3f , sizeof g);
    g[1] = 0;
    for (int i = 1; i <= k; ++i) solve(i);
    i64 answer = LLONG_MAX;
    int v = 1 , ks = 1;
    for (int i = 1; i <= n; ++i) 
        if (minimize(answer , g[i]))
            v = i - 1 , ks = i;
    cout << -g[ks] << '\n';
    vector<int> recall;
    while (k > 1)
    {
        recall.emplace_back(v);
        v = trace[k][ks] - 1;
        ks = trace[k][ks];
        --k;
    }
    reverse(recall.begin() , recall.end());
    for (auto& v : recall) cout << v << ' ';
}

Compilation message

sequence.cpp: In member function 'std::pair<long long int, int> Convex_hull::find(i64)':
sequence.cpp:58:31: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   58 |                 int mid = low + high >> 1;
      |                           ~~~~^~~~~~

Subtask #1
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 5980 KB declared answer doesn't correspond to the split scheme: declared = 114, real = 98
2 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 5980 KB declared answer doesn't correspond to the split scheme: declared = 1094451, real = 1093726
2 Halted 0 ms 0 KB -

Subtask #3
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 5980 KB declared answer doesn't correspond to the split scheme: declared = 614120000, real = 610590000
2 Halted 0 ms 0 KB -

Subtask #4
0 / 17.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 5980 KB declared answer doesn't correspond to the split scheme: declared = 21672584, real = 21418568
2 Halted 0 ms 0 KB -

Subtask #5
0 / 21.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 6628 KB declared answer doesn't correspond to the split scheme: declared = 1918678304, real = 1695400000
2 Halted 0 ms 0 KB -

Subtask #6
0 / 29.0

# Verdict Execution time Memory Grader output
1 Incorrect 25 ms 13068 KB declared answer doesn't correspond to the split scheme: declared = 21115495422, real = 19004001021
2 Halted 0 ms 0 KB -