Htykuut

Write a program to replace each string with an integer value in a given list of strings. The replacement integer value should be a sum of Ascci values of each character of the corresponding string.

list_rivers  =["Ganges", "Godavari", "Brahmaputra", "Narmada","Yamuna", "Mahanadi", "Kaveri", "Tapti"]

I tried the following which is correct but I want to optimize the code.

list_rivers  =["Ganges", "Godavari", "Brahmaputra", "Narmada", "Yamuna", "Mahanadi", "Kaveri", "Tapti"]

river =  // empty list

for i in list_rivers:

    num=0

    for j in i:

        num = num + ord(j)

    river.append(num) // [597, 813, 1143, 692, 619, 787, 610, 514]

Can anyone help how to optimize the above code?

Thanks in advance.

You can use list compréhension :

[sum([ord(i) for i in word]) for word in list_rivers]

it's equivalent to do

tmp_1 = 

for word in list_rivers:

    tmp_2 = 

    for i in word:

        tmp_2.append(ord(i))

    tmp_1.append(sum(tmp_2))

As iElden mentions, you may use list comprehension here. Note that in this case, doing so does not necessarily optimize your code for efficiency.

Your method:

%%timeit

river = 

for i in list_rivers:

    num=0

    for j in i:

        num = num + ord(j)

    river.append(num)



 # 100000 loops, best of 3: 6.57 µs per loop

List comprehension:

%%timeit

result = [sum([ord(i) for i in word]) for word in list_rivers]



# 100000 loops, best of 3: 9.37 µs per loop

(Even slower) using map:

%%timeit

result = map(lambda x: sum([ord(letter) for letter in x]), list_rivers)



# 100000 loops, best of 3: 10.3 µs per loop

It says write a program to do it, so here's a program to do so. Example output: [597, 813, 1143, 692, 619, 787, 610, 514]

def string_to_int(string):

    retval = 0

    for c in string:

        retval += ord(c)

    return retval





def main(data):

    retval = 

    for item in data:

        retval.append(string_to_int(item))

    return retval





if __name__ == "__main__":

    list_rivers = ["Ganges", "Godavari", "Brahmaputra", "Narmada", "Yamuna", "Mahanadi", "Kaveri", "Tapti"]

    results = main(list_rivers)

    print results