#!/usr/bin/env python
import sys
(numRefs, outPrefix) = sys.argv[1:]
numRefs = int(numRefs)
outs = [open(outPrefix+str(i), "w") for i in range(numRefs)]
i = 0
for line in sys.stdin:
outs[i].write(line)
i = (i + 1) % numRefs
for out in outs:
out.close()