python

uruu.py

#! /usr/bin/env python

def main():
  while True:
    year = input("年を入力:")
    if year % 4 == 0 and not year % 100 == 0 or year % 400 == 0:
      print year,"年は閏年です。"
    else if year == none:
      break
    else:
      print year,"年閏年ではありません。"

if __name__ == "__main__": main()

When you call input() it automatically evaluates the code (a security flaw). Instead, use raw_input("年を入力: ") and convert it to an integer using int()

it awesome and work nicely,