def ncalls1 (filename):
    with open (filename, 'r') as f:
        n012 = 0
        n11811 = 0
        for linia in f:
            linia = linia[:-1]
            if linia =='012':
                n012 = n012 +1
            elif linia == '11811':
                n11811 = n11811 +1
    return  n012, n11811

def ncalls2 (filename1, filename2):
    with open (filename1, 'r') as f:
        n012 = 0
        n11811 = 0
        for linia in f:
            linia = linia[:-1]
            if linia =='012':
                n012 = n012 +1
            elif linia == '11811':
                n11811 = n11811 +1
    with open (filename2,'w') as f:
        f.write ('012 '+ str(n012)+'\n')
        f.write ('11811 '+ str(n11811)+'\n')

def consecutive_numbers (filename):
    with open (filename, 'r') as f:
        prev = f.readline() # read first line
        for current in f: # continue reading from second line
            if prev == current:
                return True
            else:
                prev = current
    return False

def prefix (filename1, filename2, pref):
    with open (filename1, 'r') as f, open(filename2, 'w') as g:
        for line in f:
            if line[:len(pref)] ==pref:
                g.write(line)