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Added Lab2/Lab3 IS

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sherlock 2025-08-12 09:43:39 +05:30
parent 011d5aded1
commit 0755dd4b76
6 changed files with 109 additions and 140 deletions
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76
IS/Lab/Lab1/q1_monosub.py
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@ -5,76 +5,68 @@
def add_cipher_en(ptext, ak):
result = ""
for i in range(len(ptext)):
ch = ptext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((ord(ch) + ak - 65) % 26 + 65)
for ch in ptext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
result += chr((ord(ch) - base + ak) % 26 + base)
else:
result += chr((ord(ch) + ak - 97) % 26 + 97)
result += ch
return result
def add_cipher_de(ctext, ak):
result = ""
for i in range(len(ctext)):
ch = ctext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((ord(ch) - ak - 65) % 26 + 65)
for ch in ctext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
result += chr((ord(ch) - base - ak) % 26 + base)
else:
result += chr((ord(ch) - ak - 97) % 26 + 97)
result += ch
return result
def mult_cipher_en(ptext, mk):
result = ""
for i in range(len(ptext)):
ch = ptext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((ord(ch) * mk - 65) % 26 + 65)
for ch in ptext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
x = ord(ch) - base
result += chr((x * mk) % 26 + base)
else:
result += chr((ord(ch) * mk - 97) % 26 + 97)
result += ch
return result
def mult_cipher_de(ctext, mk):
result = ""
inverse = pow(mk, -1, 26)
for i in range(len(ctext)):
ch = ctext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((ord(ch) * inverse - 65) % 26 + 65)
for ch in ctext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
x = ord(ch) - base
result += chr((x * inverse) % 26 + base)
else:
result += chr((ord(ch) * inverse - 97) % 26 + 97)
result += ch
return result
def affine_en(ptext, ak, mk):
result = ""
for i in range(len(ptext)):
ch = ptext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((((ord(ch) - 65) * mk) + ak) % 26 + 65)
for ch in ptext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
x = ord(ch) - base
result += chr(((x * mk + ak) % 26) + base)
else:
result += chr((((ord(ch) - 97) * mk) + ak) % 26 + 97)
result += ch
return result
def affine_de(ctext, ak, mk):
result = ""
inverse = pow(mk, -1, 26)
for i in range(len(ctext)):
ch = ctext[i]
if 32 <= ord(ch) <= 47:
result += ch
elif 90 >= ord(ch) >= 65:
result += chr((((ord(ch) - 65 - ak) * inverse) % 26) + 65)
for ch in ctext:
if ch.isalpha():
base = ord('A') if ch.isupper() else ord('a')
x = ord(ch) - base
result += chr((((x - ak) * inverse) % 26) + base)
else:
result += chr((((ord(ch) - 97 - ak) * inverse) % 26) + 97)
result += ch
return result
def mult_inverse(mk):