# -*- coding: utf-8 -*-
####ID histogram

#### Exercise:
#### 
#### Write a python function
#### 
####  histogram(L)
#### 
#### where L is a list of integers. The function must return a dictionary whose keys will be precisely the integers
#### that appear in L, once each. The value of each key shall be the number of times the key appears in L. If the
#### list L is empty then so must be the dictionary returned.
#### 
#### For example, if L = [-1, 1, 0, 1, 2, -1] then the result will be the dictionary {-1: 2, 1: 2, 0: 1, 2: 1}.
#### 
#### Write your code only between the the two lines marked START and STOP below. Do not alter any of the other lines.
#### 
#### To run your program, stored in the file user.py, you give the command
#### 
####  python user.py
#### 
#### To check your program with the tester you give the command
#### 
####  python tester.py
#### 
#### or
#### 
####  python tester.py filename.py
#### 
#### if your program has been stored in filename.py.


L = input("Please give a list of integers (Python style): ")

#### Assumptions:
#### 
#### At this point the list L has been given.
#### 
#### Requirements:
#### 
#### The function histogram() that you must fill in below must compute what is described above.

#############################################################################
#### You must not give any print or input functions in your code below.
#############################################################################

#### Do not change anything down to the next line.
####START You write your code after this line.

def histogram(L):
    D = {}
    for k in L:
        if k in D:
            D[k] += 1
        else:
            D[k] = 1
    return D

####STOP Do not change anything on this line or below.
print "histogram(%r) = %r" % (L, histogram(L))