|
1 | | -/****************************************************** |
2 | | - Find and retrieve the encryption key automatically |
3 | | - Note: This is a draft version, please help to modify, Thanks! |
4 | | - ******************************************************/ |
| 1 | +/** |
| 2 | + * Find and retrieve the encryption key automatically. |
| 3 | + *@param {string} str - The input encrypted string. |
| 4 | + *@returns {number} - The encryption key found, or 0 if not found. |
| 5 | + */ |
5 | 6 | functionkeyFinder(str){ |
6 | 7 | // str is used to get the input of encrypted string |
7 | 8 | constwordBank=[ |
@@ -30,8 +31,6 @@ function keyFinder(str) { |
30 | 31 | ' be ', |
31 | 32 | 'Be ' |
32 | 33 | ] |
33 | | -// let wordbankelementCounter = 0; |
34 | | -// let key = 0; // return zero means the key can not be found |
35 | 34 | constinStr=str.toString()// convert the input to String |
36 | 35 | letoutStr=''// store the output value |
37 | 36 | letoutStrElement=''// temporary store the word inside the outStr, it is used for comparison |
@@ -59,89 +58,95 @@ function keyFinder(str) { |
59 | 58 | return0// return 0 if found nothing |
60 | 59 | } |
61 | 60 |
|
62 | | -/* this sub-function is used to assist the keyFinder to find the key */ |
| 61 | +/** |
| 62 | + * This sub-function is used to assist the keyFinder in finding the key. |
| 63 | + *@param {string} inStr - The input string. |
| 64 | + *@param {number} numShifted - The number of characters to shift in the Caesar cipher. |
| 65 | + *@returns {string} - The decrypted string. |
| 66 | + */ |
63 | 67 | functioncaesarCipherEncodeAndDecodeEngine(inStr,numShifted){ |
64 | 68 | constshiftNum=numShifted |
65 | 69 | letcharCode=0 |
66 | | -letoutStr='' |
67 | 70 | letshiftedCharCode=0 |
68 | 71 | letresult=0 |
69 | 72 |
|
70 | | -for(leti=0;i<inStr.length;i++){ |
71 | | -charCode=inStr[i].charCodeAt() |
72 | | -shiftedCharCode=charCode+shiftNum |
73 | | -result=charCode |
| 73 | +returninStr |
| 74 | +.split('') |
| 75 | +.map((char)=>{ |
| 76 | +charCode=char.charCodeAt() |
| 77 | +shiftedCharCode=charCode+shiftNum |
| 78 | +result=charCode |
74 | 79 |
|
75 | | -if(charCode>=48&&charCode<=57){ |
76 | | -if(shiftedCharCode<48){ |
77 | | -letdiff=Math.abs(48-1-shiftedCharCode)%10 |
| 80 | +if(charCode>=48&&charCode<=57){ |
| 81 | +if(shiftedCharCode<48){ |
| 82 | +letdiff=Math.abs(48-1-shiftedCharCode)%10 |
78 | 83 |
|
79 | | -while(diff>=10){ |
80 | | -diff=diff%10 |
81 | | -} |
82 | | -document.getElementById('diffID').innerHTML=diff |
| 84 | +while(diff>=10){ |
| 85 | +diff=diff%10 |
| 86 | +} |
| 87 | +document.getElementById('diffID').innerHTML=diff |
83 | 88 |
|
84 | | -shiftedCharCode=57-diff |
| 89 | +shiftedCharCode=57-diff |
85 | 90 |
|
86 | | -result=shiftedCharCode |
87 | | -}elseif(shiftedCharCode>=48&&shiftedCharCode<=57){ |
88 | | -result=shiftedCharCode |
89 | | -}elseif(shiftedCharCode>57){ |
90 | | -letdiff=Math.abs(57+1-shiftedCharCode)%10 |
| 91 | +result=shiftedCharCode |
| 92 | +}elseif(shiftedCharCode>=48&&shiftedCharCode<=57){ |
| 93 | +result=shiftedCharCode |
| 94 | +}elseif(shiftedCharCode>57){ |
| 95 | +letdiff=Math.abs(57+1-shiftedCharCode)%10 |
91 | 96 |
|
92 | | -while(diff>=10){ |
93 | | -diff=diff%10 |
94 | | -} |
95 | | -document.getElementById('diffID').innerHTML=diff |
| 97 | +while(diff>=10){ |
| 98 | +diff=diff%10 |
| 99 | +} |
| 100 | +document.getElementById('diffID').innerHTML=diff |
96 | 101 |
|
97 | | -shiftedCharCode=48+diff |
| 102 | +shiftedCharCode=48+diff |
98 | 103 |
|
99 | | -result=shiftedCharCode |
100 | | -} |
101 | | -}elseif(charCode>=65&&charCode<=90){ |
102 | | -if(shiftedCharCode<=64){ |
103 | | -letdiff=Math.abs(65-1-shiftedCharCode)%26 |
104 | | - |
105 | | -while(diff%26>=26){ |
106 | | -diff=diff%26 |
| 104 | +result=shiftedCharCode |
107 | 105 | } |
108 | | -shiftedCharCode=90-diff |
109 | | -result=shiftedCharCode |
110 | | -}elseif(shiftedCharCode>=65&&shiftedCharCode<=90){ |
111 | | -result=shiftedCharCode |
112 | | -}elseif(shiftedCharCode>90){ |
113 | | -letdiff=Math.abs(shiftedCharCode-1-90)%26 |
114 | | - |
115 | | -while(diff%26>=26){ |
116 | | -diff=diff%26 |
| 106 | +}elseif(charCode>=65&&charCode<=90){ |
| 107 | +if(shiftedCharCode<=64){ |
| 108 | +letdiff=Math.abs(65-1-shiftedCharCode)%26 |
| 109 | + |
| 110 | +while(diff%26>=26){ |
| 111 | +diff=diff%26 |
| 112 | +} |
| 113 | +shiftedCharCode=90-diff |
| 114 | +result=shiftedCharCode |
| 115 | +}elseif(shiftedCharCode>=65&&shiftedCharCode<=90){ |
| 116 | +result=shiftedCharCode |
| 117 | +}elseif(shiftedCharCode>90){ |
| 118 | +letdiff=Math.abs(shiftedCharCode-1-90)%26 |
| 119 | + |
| 120 | +while(diff%26>=26){ |
| 121 | +diff=diff%26 |
| 122 | +} |
| 123 | +shiftedCharCode=65+diff |
| 124 | +result=shiftedCharCode |
117 | 125 | } |
118 | | -shiftedCharCode=65+diff |
119 | | -result=shiftedCharCode |
120 | | -} |
121 | | -}elseif(charCode>=97&&charCode<=122){ |
122 | | -if(shiftedCharCode<=96){ |
123 | | -letdiff=Math.abs(97-1-shiftedCharCode)%26 |
124 | | - |
125 | | -while(diff%26>=26){ |
126 | | -diff=diff%26 |
127 | | -} |
128 | | -shiftedCharCode=122-diff |
129 | | -result=shiftedCharCode |
130 | | -}elseif(shiftedCharCode>=97&&shiftedCharCode<=122){ |
131 | | -result=shiftedCharCode |
132 | | -}elseif(shiftedCharCode>122){ |
133 | | -letdiff=Math.abs(shiftedCharCode-1-122)%26 |
134 | | - |
135 | | -while(diff%26>=26){ |
136 | | -diff=diff%26 |
| 126 | +}elseif(charCode>=97&&charCode<=122){ |
| 127 | +if(shiftedCharCode<=96){ |
| 128 | +letdiff=Math.abs(97-1-shiftedCharCode)%26 |
| 129 | + |
| 130 | +while(diff%26>=26){ |
| 131 | +diff=diff%26 |
| 132 | +} |
| 133 | +shiftedCharCode=122-diff |
| 134 | +result=shiftedCharCode |
| 135 | +}elseif(shiftedCharCode>=97&&shiftedCharCode<=122){ |
| 136 | +result=shiftedCharCode |
| 137 | +}elseif(shiftedCharCode>122){ |
| 138 | +letdiff=Math.abs(shiftedCharCode-1-122)%26 |
| 139 | + |
| 140 | +while(diff%26>=26){ |
| 141 | +diff=diff%26 |
| 142 | +} |
| 143 | +shiftedCharCode=97+diff |
| 144 | +result=shiftedCharCode |
137 | 145 | } |
138 | | -shiftedCharCode=97+diff |
139 | | -result=shiftedCharCode |
140 | 146 | } |
141 | | -} |
142 | | -outStr=outStr+String.fromCharCode(parseInt(result)) |
143 | | -} |
144 | | -returnoutStr |
| 147 | +returnString.fromCharCode(parseInt(result)) |
| 148 | +}) |
| 149 | +.join('') |
145 | 150 | } |
146 | 151 |
|
147 | 152 | export{keyFinder} |
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