I am working on a very basic problem on Hackerrank.
Input format:
First line contains integer N.
Second line contains string S.
Output format:
First line should contain N x 2.
Second line should contain the same string S.
sample test case
5
helloworld
my code is as: (on PYTHON 3)
n=int(input())
s=input()
print(2*n)
print(s)
I am getting error:
Execution failed.
EOFError : EOF when reading a line
Stack Trace:
Traceback (most recent call last):
File "/tmp/143981299/user_code.py", line 1, in <module>
N = int(input())
EOFError: EOF when reading a line
I tried this method to take input many times and this is the first time I am having this error. Can anyone please explain why?
use a try/except block to handle the error
while True:
try:
n=int(input())
s=input()
print(2*n)
print(s)
except:
break
Related
I try to learn this book under python-3 environment but it pops out an error when I try to run it. Is there anywhere to fix this?
Once I deleted
print("Ready, hit RETURN to continue, CTRL-C to abort.")
input()
The code ran perfectly. So I think it should be the syntax problem between python 2 and python 3
from sys import argv
from os.path import exists
script, from_file, to_file = argv
print("Copying from %s to %s" % (from_file,to_file))
# we could do these two on one line too, how?
in_file = open(from_file)
indata = in_file.read()
print("The input file is %d bytes long" % len(indata))
print("Does the output file exist? %r" % exists(to_file))
print("Ready, hit RETURN to continue, CTRL-C to abort.")
input()
out_file = open(to_file, 'w')
out_file.write(indata)
print("Alright, all done")
out_file.close()
in_file.close()
When I try to run it, it should stops at input() and wait me hit the return key to continue. But in reality, the code stopped and an error called
"Traceback (most recent call last):
File "ex17.2.py", line 18, in <module> g
input("")
File "<string>", line 0
^
SyntaxError: unexpected EOF while parsing
popped out.
Yes you are correct!! The error you are getting is due to python version change. This code works perfectly fine in python 3.x but fails in python version under 3.x.
Hope this helps.
Question-
https://www.codechef.com/problems/SINS
Compiler used-
https://www.codechef.com/ide
Input method-
Custom input of codechef compiler.
My attempt-
T=int(input())
def fnc(a,b):
if b!=0:
return fnc(b,a%b)
else:
return int(a*2)
while T>0:
X,Y=map(int,input().split())
if X==0:
print(Y)
elif Y==0:
print(X)
elif X==Y:
print(X*2)
else:
f=fnc(X,Y)
print(f)
T=T-1
Issue:
I am getting the following runtime error:
Traceback (most recent call last):
File "./prog.py", line 8, in <module>
EOFError: EOF when reading a line
The output is correct but still there is this runtime error.
That is because the input() is getting End Of File (I assume you are using Python 3). You need to trap the EOFError exception and break out of the loop when you get it. You asked what I meant by that comment, this is what I mean:
try:
X, Y = map(int, input().split())
except EOFError:
break
elif(ch==2):
fh=open("emp1.txt","rb+")
fo=open("temp.txt","wb+")
ecode=input("Enter the Ecode :")
rec=(" ")
try:
while True:
emp1= pickle.load(fh)
if (emp1.ecode!=ecode):
pickle.dump(emp1,fh)
except(EOFError):
fh.close()
fo.close()
os.remove("empl.txt")
os.rename("temp.txt","emp1.txt")
print("")
running the following code gives me this error:
Traceback (most recent call last): File
"C:\Users\hello\Desktop\bhavi\python programming\Employ.py", line 78,
in
emp1= pickle.load(fh) EOFError
During handling of the above exception, another exception occurred:
Traceback (most recent call last): File
"C:\Users\hello\Desktop\bhavi\python programming\Employ.py", line 85,
in
os.remove("empl.txt") FileNotFoundError: [WinError 2] The system cannot find the file specified: 'empl.txt'
What should i do now??
You should fix your path. In the first case, you write "emp1.txt"; and in the second, you write "empl.txt". If you look carefully, you should notice that there is a difference in those two strings.
Hint: '1' != 'l'
Your code could probably be refactored as well. While it is not possible for others to test your code since it is very incomplete, the following should work in its place. You will still need to verify it works.
elif ch == 2:
with open('emp1.txt', 'rb+') as fh, open('temp.txt', 'wb+') as fo:
ecode = input('Enter the Ecode: ')
while True:
try:
item = pickle.load(fh)
except EOFError:
break
else:
if item.ecode != ecode:
pickle.dump(item, fo)
os.remove(fh.name)
os.rename(fo.name, fh.name)
print()
I would use shelve, its much easier to use and it doesn't come up with to many errors in my experience. shelve is built on pickle but it just simplify it.
here is a short tutorial
http://python.wikia.com/wiki/Shelve
Code :
n,X=input(),0
for t in range(int(n)):
eval(input())
print(X)
Traceback (most recent call last):
File "prog.py", line 3, in <module>
eval(input())
File "<string>", line 1
X++
^
SyntaxError: unexpected EOF while parsing
Using raw_input instead of input() in the only solution I am able to find but in python 3.x input is raw_input(): How do I use raw_input in Python 3
any other method?
FYI; I am trying to solve: http://codeforces.com/problemset/problem/282/A
Remove the eval() call.
input() in Python 2 is the equivalent of eval(input()) in Python 3, and if you need to use raw_input() in Python 2 then in Python 3 you need to remove the eval() call.
You'll have to parse the input yourself; ++ is not a valid Python operator, you cannot use eval() to solve that Codeforces problem.
The simplest way to solve the posted problem is to read the input line by line:
import sys, itertools
count = int(next(sys.stdin))
x = 0
for line in itertools.islice(sys.stdin, count):
x += 1 if '++' in line else -1
print(x)
I have a problem with the following code:
inputf = open('test.dat', 'r')
lines = inputf.readlines()
rico_clus_e = []
for line in lines:
line.split()
print line
if (line[0] != '#'):
rico_clus_e.append(float(line[4]))
inputf.close()
My test.dat file is:
# specn rico_all rico_all_e rico_clus rico_clus_e rico_farclust rico_far_e extin
a119 1.07038692 0.11109547 0.61473431 0.15063627 0.32590239 0.14777812 0.207
And this gives the following output in my terminal:
# specn rico_all rico_all_e rico_clus rico_clus_e rico_farclust rico_far_e extin
a119 1.07038692 0.11109547 0.61473431 0.15063627 0.32590239 0.14777812 0.207
Traceback (most recent call last):
File "test.py", line 8, in <module>
rico_clus_e.append(float(line[4]))
ValueError: could not convert string to float:
I'm quite confused by this. It had nothing to do with spaces, I checked them all. And if you change 4 by 1, 2 or 3 this works, so it must have something to do with the test.dat file, but I can't seem to figure out how. I'm using python 2.7.3.
line.split() on its own does nothing to line. You must store the result of the method call and use that instead.