import os,re,string

def steiner(points):
    [fin,fout]=os.popen2('steiner','t')

    fin.write('2\n')
    fin.write(str(len(points))+'\n')
    fin.write('1\n')
    for point in points:
        fin.write(str(long(point[0]))+' '+str(long(point[1]))+'\n')
    fin.close()

    line=fout.readline()
    line=fout.readline()
    m = re.search(r"ST_cost\s+(\d+)",line)
    if m:
        val=string.atol(m.group(1))
    else:
        print 'ERROR: Could not find return value of steiner program\n'
    fout.close()

    return val


p = [ [1,2],[2,4],[4,1],[5,3] ]
cost=steiner(p)
print 'Minimum Steiner Tree Cost:',cost