buu crypto variation caesar

1. From the title, we can see that it is Caesar encryption, but it is mutated, indicating that there is a change, but the essential shift of Caesar is unchanged. Compare the ciphertext afZ_r9VYfScOeO_UL ^ RWUc with flag. Check the character table and find
a: 97 f: 102
f: 102 l: 107
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Description Moves 5 digits and 6 digits back in sequence. . . . Bit
Two. Code

str="afZ_r9VYfScOeO_UL^RWUc"
i =5
flag=""
for s in str:
    flag+=chr(ord(s)+i)
    i+=1
print(flag)