Edit distance

import fileinput

def edit_distance(first, second):
    if first == second:
        return 0
    len_first, len_second = len(first), len(second)
    cur = list(range(0, len_first + 1))
    for i in range(1, len_second+1):
        prev, cur = cur, [i] + [0]*len_first
        for j in range(1, len_first+1):
            a, d, c = prev[j]+1, cur[j-1]+1, prev[j-1]
            if first[j-1] != second[i-1]:
                c += 1
            cur[j] = min(a, d, c)
    return cur[len_first]


if __name__ == '__main__':
    with fileinput.input(['-']) as input:
        string_1 = input.readline().rstrip()
        string_2 = input.readline().rstrip()
        d = len(string_1) - len(string_2)
        if d > 0:
            string_1 = string_1[:len(string_2)]
        elif d < 0:
            string_2 = string_2[:len(string_1)]
        print(edit_distance(string_1, string_2) + abs(d))

Test 1

Verdict: UNKNOWN

Test 2

Verdict: UNKNOWN

Test 3

Verdict: UNKNOWN

Test 4

Verdict: UNKNOWN

Test 5

Verdict: UNKNOWN

Test 6

Verdict: UNKNOWN

Test 7

Verdict: UNKNOWN

Test 8

Verdict: UNKNOWN

Test 9

Verdict: UNKNOWN

Test 10

Verdict: UNKNOWN

Test 11

Verdict: UNKNOWN

Test 12

Verdict: UNKNOWN

Test 13

Verdict: UNKNOWN

Test 14

Verdict: UNKNOWN

Test 15

Verdict: UNKNOWN

Test 16

Verdict: UNKNOWN

Test 17

Verdict: UNKNOWN

Test 18

Verdict: UNKNOWN

Test 19

Verdict: UNKNOWN