为什么 split 和 readlines 会中断循环？

Question

In our Python course, we were given this problem. We need to get accounts data from a file, perform some manipulations, and output the results... I've tried to use the first value of the account as an initial minimum. It's not working. It does something I have no idea and just shuts off entire for loop.

accounts.txt is a file that stores ID, savings type, and value. For example,

66096   d   873323
29615   c   849977
45387   s   186640
95384   c   933363
13615   c   733321
46396   c   714610
17428   s   833671
43730   d   308296
92061   c   670423
51798   c   156063
58083   s   940510

So, here's the code:

file=open('accounts.txt',mode='r')
linep=file.readlines()
mins=linep[0].split()[2]
sumc=0
maxc=0
sums=0
sumd=0
avrd=0
cntr=0
for i in file:
    if i.split()[1]=='c':
        sumc+=int(i.split()[2])
        if int(i.split()[2])>=maxc:
            maxc=int(i.split()[2])
    elif i.split()[1]=='s':
        sums+=int(i.split()[2])
        if int(i.split()[2])<=mins:
            mins=int(i.split()[2])
    elif i.split()[1]=='d':
        sumd+=int(i.split()[2])
        cntr+=1
avrd=sums/cntr
print('The sum of all checking accounts is:',sumc)
print('The sum of all saving accounts is:',sums)
print('The sum of all deposit accounts is:',sumd)
print('The maximum balance for all checking accounts is:',maxc)
print('The minimum balance for all savings accounts is:',mins)
print('The average balance for all deposit accounts is:',avrd)

It works when you set the mins=99999999999 , but I don't think that's a good solution.

Well, the output should've been like this:

The sum of all checking accounts is: 209315463
The sum of all saving accounts is: 50272914
The sum of all deposit accounts is: 19976046
The maximum balance for all checking accounts is: 998992
The minimum balance for all savings accounts is: 150
The average balance for all deposit accounts is: 554890.1666666666

But 2nd & 3rd lines screw everything up, so I have this

The sum of all checking accounts is: 0
The sum of all saving accounts is: 0
The sum of all deposit accounts is: 0
The maximum balance for all checking accounts is: 0
The minimum balance for all savings accounts is: 873323

So, what do you think? I know, you can use min and max, but that's college we are talking about. They want to do it this way.

Answer 1

Minimal changes to correct your code

file=open('accounts.txt',mode='r')
linep=file.readlines()
mins=int(linep[0].split()[2])  # Need to make int
sumc=0
maxc=0
sums=0
sumd=0
avrd=0
cntr=0
for i in linep:  # need to loop over linep not file
    if i.split()[1]=='c':
        sumc+=int(i.split()[2])
        if int(i.split()[2])>=maxc:
            maxc=int(i.split()[2])
    elif i.split()[1]=='s':
        sums+=int(i.split()[2])
        if int(i.split()[2])<=mins:
            mins=int(i.split()[2])
    elif i.split()[1]=='d':
        sumd+=int(i.split()[2])
        cntr+=1
avrd=sums/cntr
print('The sum of all checking accounts is:',sumc)
print('The sum of all saving accounts is:',sums)
print('The sum of all deposit accounts is:',sumd)
print('The maximum balance for all checking accounts is:',maxc)
print('The minimum balance for all savings accounts is:',mins)
print('The average balance for all deposit accounts is:',avrd)

Code Refactoring (simpler and more efficient)

file=open('accounts.txt',mode='r')
linep=file.readlines()
data = [x.split() for x in linep]
checking = [int(x[2]) for x in data if x[1] == 'c']
savings = [int(x[2]) for x in data if x[1] == 's']
deposits = [int(x[2]) for x in data if x[1] == 'd']
sumc, sums, sumd = sum(checking), sum(savings), sum(deposits)
maxc, mins, avrd = max(checking), min(savings), sum(deposits)/len(deposits)
print('The sum of all checking accounts is:',sumc)
print('The sum of all saving accounts is:',sums)
print('The sum of all deposit accounts is:',sumd)
print('The maximum balance for all checking accounts is:',maxc)
print('The minimum balance for all savings accounts is:',mins)
print('The average balance for all deposit accounts is:',avrd)