Need for Shift

Molly has a habit of shifting. She shifts letters of a string certain number of times. She takes any string and shifts back each letter of the string alphabetically. For example, if she shifts letters of string 'dcoder' 1 time, it becomes 'cbncdq',i.e, all letters of the string are shifted back by one. In case of presence of 'a', it is shifted back in a circular manner to 'z'. You will be given a string, print the changed string after Molly's shifting.
Input

A single string and a single positive integer D in the next line. D denotes the number of times we have to shift back.
Output

Print the converted string after Molly's Shifting.
Contraints

1 ≤ string.length ≤ 50
1 ≤ D ≤ 100
All characters of the string will be in lowercase.
Sample Input

bcde
Sample Output

abcd
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