Cod sursa(job #3243807)

Utilizator puica2018Puica Andrei puica2018 Data 21 septembrie 2024 14:04:14
Problema Lapte Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.92 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("lapte.in");
ofstream fout("lapte.out");

int n,l;

int a[105],b[105];

int lim[105];

int dp[105][105];

pair <int,int> best[105][105];

vector <pair <int,int>> aux1;

bool f(int T)
{
    for(int k=0; k<=n; k++)
        for(int i=0; i<=l; i++)
            dp[k][i]=-1;

    dp[0][0]=0;
    for(int k=1; k<=n; k++)
    {
        for(int i=0; i<=l; i++)
        {
            lim[i]=-1;

            for(int j=0; j<=l; j++)
                if(i*a[k]+j*b[k]<=T)
                    lim[i]=j;
        }

        for(int ii=0; ii<=l; ii++)
        {
            for(int i=0; i<=l; i++)
            {
                if(dp[k-1][ii]>=0 && lim[i]>=0 && i+ii<=l)
                {
                    if(dp[k-1][ii]+lim[i]>dp[k][i+ii])
                    {
                        dp[k][i+ii]=dp[k-1][ii]+lim[i];

                        best[k][i+ii]=make_pair(i,lim[i]);
                    }
                }
            }
        }
    }

    aux1.clear();
    int k=n,i=l;
    while(k>=1)
    {
        aux1.push_back(best[k][i]);
        i-=best[k][i].first;
        k--;
    }

    return (dp[n][l]>=l);
}

int main()
{
    fin>>n>>l;
    for(int i=1; i<=n; i++)
        fin>>a[i]>>b[i];

    vector <pair <int,int>> aux2;

    int st=1,dr=100,mij,T=0;
    while(st<=dr)
    {
        mij=(st+dr)/2;

        if(f(mij)==1)
        {
            aux2=aux1;
            T=mij;
            dr=mij-1;
        }
        else
        {
            st=mij+1;
        }
    }

    reverse(aux2.begin(),aux2.end());

    fout<<T<<"\n";

    for(auto it:aux2)
    {
        if(l>=it.second)
        {
            fout<<it.first<<" "<<it.second<<"\n";
            l-=it.second;
        }
        else
        {
            fout<<it.first<<" "<<l<<"\n";
            l=0;
        }
    }

    return 0;
}