oj.uz

Submission #580053

# Submission time Handle Problem Language Result Execution time Memory
580053 2022-06-20T14:12:33 Z wdjpng Boarding Passes (BOI22_passes) C++17
5 / 100
 4 ms 1612 KB 
#include <bits/stdc++.h>

#define int long long
#define double long double
#define rep(i,n) for(int i =0; i<n; i++)
#define all(a) a.begin(),a.end()

using namespace std;


string s;
int n;
double f(int n)
{
    return ((double) n)*((double) (n-1))/4.0;
}

string ord;
vector<double>mem;
vector<vector<int>>pos;
int g;
// cost to add the group gr with all members of that group with and index <= to i boarding on the left
double cost(int bor, int gr, int i)
{
    vector<int>pref;

    double sum = 0;
    int firstr = upper_bound(all(pos[gr]),i) - pos[gr].begin();

    sum+=f(pos[gr].size()-firstr) + f(firstr);

    return sum;
}

double dfs(int bor)
{
    if(mem[bor]>-0.9) return mem[bor];

    int tmp = 0;
    rep(i,g) if((1<<i)&bor) tmp++;
    if(tmp==1) return f(n/2) + f((n+1)/2);

    double sol = 1e18;
    rep(i,g)
    {
        if(!((1<<i)&bor)) continue;
        int nbor = bor^(1<<i);
        int start = 0, end = n;
        while (end-start>1)
        {
            int c = (start+end)/2;
            if(cost(nbor,i,c)>cost(nbor,i,c+1)) start=c;
            else end=c;
        }
        sol=min(sol, cost(nbor,i,start));
    }
    return mem[bor] = sol;
}
signed main()
{
    cin>>s;
    s.size();
    n=s.size();

    double sum = f(n/2) + f((n+1)/2);
    cout.precision(300);
    
    char maxx=0;
    rep(i,n) maxx=max(maxx, s[i]);
    g='A'-maxx+1;

    pos.resize(g);
    mem.assign(1<<g,-1.0);
    rep(i,n) pos[(s[i]-'A')].push_back(i);

    cout<<dfs((1<<g)-1)<<'\n';
}

Compilation message

passes.cpp: In function 'int main()':
passes.cpp:65:12: warning: unused variable 'sum' [-Wunused-variable]
   65 |     double sum = f(n/2) + f((n+1)/2);
      |            ^~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 4 ms 1484 KB Output is correct
7 Correct 4 ms 1612 KB Output is correct
8 Correct 4 ms 1612 KB Output is correct
9 Correct 4 ms 1548 KB Output is correct

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Runtime error 2 ms 468 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Runtime error 2 ms 468 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 4 ms 1484 KB Output is correct
7 Correct 4 ms 1612 KB Output is correct
8 Correct 4 ms 1612 KB Output is correct
9 Correct 4 ms 1548 KB Output is correct
10 Runtime error 2 ms 468 KB Execution killed with signal 6
11 Halted 0 ms 0 KB -