Cod sursa(job #1813796)

Utilizator RaduMirceaAndreiRadu Mircea Andrei RaduMirceaAndrei Data 23 noiembrie 2016 12:16:41
Problema Ciclu hamiltonian de cost minim Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
# include <fstream>
# define N 18
# define DIM 1<<18
# define INF 1000000000
using namespace std;
ifstream fin("hamilton.in");
ofstream fout("hamilton.out");
int v[DIM][N],c[N][N],rv[DIM],n,m,i,j,q,t,x,y,cost,a,b,sol;
int main () {
    fin>>n>>m;
    for(i=1,j=0;i<(1<<n);i*=2,j++)
        rv[i]=j;
    for(i=1;i<=m;i++){
        fin>>x>>y>>cost;
        c[x][y]=cost;
    }
    for(i=1;i<(1<<n);i++)
        for(j=0;j<n;j++)
           v[i][j]=INF;
    v[1][0]=0;
    for(i=1;i<(1<<n);i++){
        q=(1<<n)-i;
        for(j=i;j>=1;j-=(j&(-j))){
            a=rv[(j&(-j))];
            if(v[i][a]!=INF){
                for(t=q;t>=1;t-=(t&(-t))){
                    b=rv[(t&(-t))];
                    if(c[a][b])
                        v[i+(t&(-t))][b]=min(v[i+(t&(-t))][b],v[i][a]+c[a][b]);
                }
            }
        }
    }
    sol=INF;
    for(i=1;i<n;i++)
        if(c[i][0])
            sol=min(sol,v[(1<<n)-1][i]+c[i][0]);
    fout<<sol<<"\n";
    return 0;
}