Cod sursa(job #827060)

Utilizator BeilandArnoldArnold Beiland BeilandArnold Data 1 decembrie 2012 16:16:07
Problema Elimin Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.41 kb
#include <fstream>
#include <vector>
#include <limits>
#include <algorithm>

inline void parsare(unsigned *psmax, unsigned short r,const std::vector<short> &ci,
                    const std::vector< std::vector<unsigned short> > &matrice, bool flag);
inline bool inci(unsigned short i, const std::vector<short> &ci);

int main(){
    std::ifstream fin("elimin.in");
    std::ofstream fout("elimin.out");
    unsigned short m,n,r,c;
    fin>>m>>n>>r>>c;
    bool inv=false;
    if(m<n){inv=true; unsigned short temp=m; m=n; n=temp; temp=r; r=c; c=temp;}
    std::vector< std::vector<unsigned short> > matrice(n,std::vector<unsigned short>(m));
    if(inv)
        for(unsigned short ci=0;ci<n;ci++)
            for(unsigned short ri=0;ri<m;++ri)
                fin>>matrice[ci][ri];
    else
        for(unsigned short ri=0;ri<m;++ri)
            for(unsigned short ci=0;ci<n;ci++)
                fin>>matrice[ci][ri];
    //n,c
    unsigned smax=0;
    if(c==0) parsare(&smax,r,std::vector<short>(),matrice,false);
    else{
        bool reverse=false;
        if(c>(n/2)){ reverse=true; c = n-c; }
        short i=0;
        std::vector<short> ci(c,-1);
        while(i>-1){
            if(ci[i]==n-c+i) ci[i--]=-1;
            else{
                if(i==0) ci[i]++;
                else if(ci[i]==-1) ci[i]=ci[i-1]+1;
                else ci[i]++;
                if(i==c-1) parsare(&smax,r,ci,matrice,reverse);
                else i++;
            }
        }
    }
    fout<<smax<<'\n';
}
inline void parsare(unsigned *psmax, unsigned short r,const std::vector<short> &ci,
                    const std::vector< std::vector<unsigned short> > &matrice, bool flag){
    std::vector<unsigned> rowssums(matrice[0].size(),0);
    for(unsigned short i=0;i<matrice.size();++i)
        if(flag==inci(i,ci)) for(unsigned j=0;j<matrice[0].size();++j) rowssums[j]+=matrice[i][j];
    std::sort(rowssums.begin(),rowssums.end());
    unsigned totalrows=0;
    for(unsigned i=r;i<rowssums.size();++i) totalrows+=rowssums[i];
    if(totalrows>*psmax) *psmax=totalrows;
}
inline bool inci(unsigned short i, const std::vector<short> &ci){ //based on binary search
    unsigned short pos=0, step;
    for(step=1;step<ci.size();step<<=1);
    step>>=1;
    for(;step;step>>=1){
        if(((pos|step)<ci.size())&&(ci[pos|step]<=i)) pos|=step;
    }
    if(ci[pos]==i) return true;
    else return false;
}