Submission #581189

#	Time	Username	Problem	Language	Result	Execution time	Memory
581189		wdjpng	Boarding Passes (BOI22_passes)	C++17	60 / 100	2088 ms	13520 KiB

passes

#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;
vector<vector<vector<int>>>insleft(15,vector<vector<int>>(15)), insright(15,vector<vector<int>>(15));

int g;
// cost to add the group gr with all members of that group with and index <= to maxi boarding on the left
double cost(int bor, int gr, int firstr)
{
    double sum = 0;

    sum+=f(pos[gr].size()-firstr) + f(firstr);
    rep(i,g) if(((1<<i)&bor)==0) sum+=insleft[gr][i][firstr]+insright[gr][i][firstr];
    return sum;
}

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


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


signed main()
{
    cin>>s;
    s.size();
    n=s.size();

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

    pos.resize(g);
    rep(i,n) pos[(s[i]-'A')].push_back(i);
    
    rep(gr,g)
    {
        rep(i,g)
        {
            if(i==gr) continue;
            insleft[gr][i].assign(pos[gr].size()+1,0);
            insright[gr][i].assign(pos[gr].size()+1,0);
            for(int firstr=1; firstr <= pos[gr].size(); firstr++) 
            {
                insleft[gr][i][firstr]=insleft[gr][i][firstr-1];
                while (insleft[gr][i][firstr]<pos[i].size()&&pos[i][insleft[gr][i][firstr]]<pos[gr][firstr-1]) insleft[gr][i][firstr]++;
            }
            for(int firstr=pos[gr].size()-1; firstr >= 0; firstr--)
            {
                insright[gr][i][firstr]=insright[gr][i][firstr];
                while (insright[gr][i][firstr]<pos[i].size()&&pos[i][pos[i].size()-1-insright[gr][i][firstr]]>pos[gr][firstr]) insright[gr][i][firstr]++;
            }
            rep(j,pos[gr].size()) insleft[gr][i][j+1]+=insleft[gr][i][j];
            for(int j=pos[gr].size()-2; j>=0; j--) insright[gr][i][j]+=insright[gr][i][j+1];
        }
    }

    lookup.assign(g,0);
    rep(i,g) lookup[i]=i;
    mem.assign(1<<g,-1.0);
    mem[0]=0;
    cout<<dfs((1<<g)-1)<<'\n';
}

Compilation message (stderr)

passes.cpp: In function 'int main()':
passes.cpp:84:38: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |             for(int firstr=1; firstr <= pos[gr].size(); firstr++)
      |                               ~~~~~~~^~~~~~~~~~~~~~~~~
passes.cpp:87:46: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |                 while (insleft[gr][i][firstr]<pos[i].size()&&pos[i][insleft[gr][i][firstr]]<pos[gr][firstr-1]) insleft[gr][i][firstr]++;
passes.cpp:92:47: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<long long int>, long long int>::value_type' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   92 |                 while (insright[gr][i][firstr]<pos[i].size()&&pos[i][pos[i].size()-1-insright[gr][i][firstr]]>pos[gr][firstr]) insright[gr][i][firstr]++;
passes.cpp:5:33: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    5 | #define rep(i,n) for(int i =0; i<n; i++)
......
   94 |             rep(j,pos[gr].size()) insleft[gr][i][j+1]+=insleft[gr][i][j];
      |                 ~~~~~~~~~~~~~~~~ 
passes.cpp:94:13: note: in expansion of macro 'rep'
   94 |             rep(j,pos[gr].size()) insleft[gr][i][j+1]+=insleft[gr][i][j];
      |             ^~~

• Subtask 1: 5 / 5
• Subtask 2: 25 / 25
• Subtask 3: 30 / 30
• Subtask 4: 0 / 40