功能要求：
1.額度15000
2.可以體現，手續費是5%
3每月最後一天是出賬單，寫入一個文件
4.記錄每月日常消費流水（每天的沒筆消費）
5.寫出來本期還款
python源代碼：
#!/usr/bin/env python
# encoding=utf-8
# author:sihaogongyuan
# date:2015-4-13
# filename:atm-py
# desc:atm-py
#################################################
import sys
import os
sys.path.append('/tmp/python/')
import tab
import time
#################################################
credit_line=int(15000)
old_money=int(15000)
#print type(credit_line)
#counter_fee=0.05
fee_rate=0.05
#################################################
#date=time.strftime('%Y-%m-%d %H:%M:%S')
#################################################
date1=time.strftime('%Y-%m-%d-%H:%M:%S')
f=file('%s.log'%(date1),'w')
f.close()
f=file('%s.log'%(date1),'a')
f.write('交易日期\t交易摘要\t金額\t手續費\t信用額度\n')
#######取現######################################
def qu_xian():
global credit_line
global fee_rate
#date=os.system("date '+%F:%T'")
#print date
date=time.strftime('%Y-%m-%d %H:%M:%S')
quxian_money=int(raw_input('請輸入取現金額:').strip())
#print quxian_money,type(quxian_money)
while quxian_money=='':
continue
#print quxian_money,type(quxian_money)
if 0<quxian_money<=credit_line:
#定義手續費counter_fee
counter_fee=quxian_money*fee_rate
credit_line=credit_line-quxian_money-counter_fee
print '\033[32m已取%d元,手續費是%d元,信用額度是%d元\033[0m'%(quxian_money,counter_fee,credit_line)
f.write('%s\t取現\t%s\t%d\t%d\n'%(date,quxian_money,counter_fee,credit_line))
f.flush()
else:
print '\033[31m取現金額%d不在信用額度內,取現失敗\033[0m'%(quxian_money)
#######刷卡########################################
def shua_ka():
global credit_line
#date=os.system("date '+%F:%T'")
date=time.strftime('%Y-%m-%d %H:%M:%S')
shuaka_money=int(raw_input('請輸入消費金額:').strip())
if 0<shuaka_money<=credit_line:
credit_line=credit_line-shuaka_money
print '\033[32m已消費%d元,信用額度是%d元\033[0m'%(shuaka_money,credit_line)
#f.write(os.system('date'),'\t','刷卡','\t',shuaka_money,0)
f.write('%s\t刷卡\t%s\t0\t%d\n'%(date,shuaka_money,credit_line))
f.flush()
else:
print '\033[31m消費金額%d不在信用額度內,消費失敗\033[0m'%(shuaka_money)
########存錢#######################################
def cun_qian():
global credit_line
#date=os.system("date '+%F:%T'")
date=time.strftime('%Y-%m-%d %H:%M:%S')
cun_qian_money=int(raw_input('請輸入存錢金額:').strip())
if cun_qian_money>0:
credit_line=credit_line+cun_qian_money
print '\033[32m存款%d成功，目前信用額度是:%d'%(cun_qian_money,credit_line)
f.write('%s\t存錢\t-%s\t0\t%d\n'%(date,cun_qian_money,credit_line))
f.flush()
else:
print '\033[31m存取金額%d不符合規範，存款失敗\033[0m'%(cun_qian_money)
###########main####################################
print '\t歡迎來到ATM系統'
while True:
#credit_line=int(15000)
#fee_rate=0.05
choice=raw_input('請輸入你要進行的操作(取現,消費,存錢,退出):').strip()
if choice=='':
continue
if choice=='取現' or choice=='提現':
qu_xian()
continue
elif choice=='刷卡' or choice=='消費':
shua_ka()
continue
elif choice=='存錢' or choice=='存款':
cun_qian()
continue
elif choice=='退出' or choice=='exit':
break
else:
print '不合規的操作，請重新選擇'
continue
###################################################
f.write('\033[32m目前可用信用額度爲:%s\n\033[0m'%(credit_line))
f.flush()
f.write('\033[32m本期還款金額爲%d\n\033[0m'%(old_money-credit_line))
f.flush()
f.close()
f=file('%s.log'%(date1),'r')
print f.read()
###################################################