用JAVA写的一个破解Vigenere的程序,运行成功,但是没有结果.不知道为什么....
Exception in thread "main " java.lang.ArrayIndexOutOfBoundsException: 6
at Vigenere.figureOutKeyLength(DecoderAndEncoder.java:74)
at DecoderAndEncoder.main(DecoderAndEncoder.java:38)
Java Result: 1
debug-single:
生成成功（总时间：1 秒）
import java.util.*;
import java.text.*;
public class DecoderAndEncoder {
/** Creates a new instance of DecoderAndEncoder */
public static void main(String[] args)
{
String originalCode= "hdsfgvmkoowafweetcmfthskucaqbil " +
"gjofmaqlgspvatvxqbiryscpcfrmvswrvnqlszdmgao " +
"qsakmlupsqforvtwvdfcjzvgsoaoqsacjkbrsevbelv " +
"bksarlscdcaarmnvrysywxqgvellcyluwwveoafgcla " +
"zowafojdlhssfiksepsoywxafowlbfcsocylngqsyzx " +
"gjbmlvgrggokgfgmhlmejabsjvgmlnrvqzcrggcrghg " +
"eupcyfgtydycjkhqluhgxgzovqswpdvbwsffsenbxap " +
"asgazmyuhgsfhmftayjxmwznrsofrsoaopgauaaarmf " +
"tqsmahvqecev ";//要破译的密文
int[] statu=new int[6];
Vigenere myCode=new Vigenere(originalCode);
for(int i=0;i <6;i++)
{
String temp=myCode.moveLeft(i);
statu[i]=myCode.compareIt(originalCode,temp);
}
keyLength=myCode.figureOutKeyLength(statu);//報錯說這一行也有錯誤
int[] key=new int[keyLength];
for(int j=0;j <keyLength;j++)
{
key[j]=myCode.findKey(j,keyLength);
}
String enCode=myCode.deCoder(key,keyLength);
System.out.println( "解密后的明文为: ");
System.out.println(enCode);
}
private static int keyLength;
}
class Vigenere{
public Vigenere(String s)
{
oril=s;
}
public String moveLeft(int k)
{
String str=oril.substring(k,oril.length());
return str;
}
public int compareIt(String m,String n)
{
int p=0;
for(int q=0;q <n.length();q++)
{
if(m.charAt(q)==n.charAt(q)) p++;
}
return p;
}
public int figureOutKeyLength(int[] t)
{
int u=0;
for(int r=0;r <t.length;r++)
{
if(t[r]> t[r+1]) u=r;//報錯說這一行有錯誤
else u=r+1;
}
return u;
}
public int findKey(int v,int z)
{
double[][] A=new double[26][26];
A[0]=new double[]{0.082,0.015,0.028,0.043,0.0127,0.022,0.020,0.061,0.070,
0.002,0.008, 0.040,0.024,0.067,0.075,0.019,0.001,0.060,
0.063,0.091,0.028 ,0.010,
0.023 ,0.001,0.020,0.001};
for(int c=0;c <26;c++)
{
for(int d=1;d <26;d++)
A[c+1][d-1]=A[c][d];
A[c+1][25]=A[c][0];
}
int[] V=new int[]{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
double[] W=new double[26];
int g=0;
String alphaBeta= "abcdefghijklmnopqrstuvwxyz ";
for(int j=0;j <26;j++)
for(g=v;g <oril.length();g+=z)
{
if(oril.charAt(g)==alphaBeta.charAt(j))
V[j]++;
}
for(int h=0;h <26;h++)
{
W[h]=V[h]/g;
}
double[] WA=new double[]{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
for(int k=0;k <26;k++)
{
for(int n=0;n <26;n++)
WA[k]+=A[k][n]*W[n];
}
int key=0;
for(int i=0;i <26;i++)
{
if(WA[i]> WA[i+1]) key=i;
else key=i+1;
}
return key;
}
public String deCoder(int[] key,int keyLength)
{
String enCode= " ";
char s;
for(int i=0;i <oril.length();i++)
{ char c=oril.charAt(i);
c+=(key[i%keyLength]);
s=(char)c;
enCode+=s;
}
return enCode;
}
private String oril;
}
[解决办法]
r = t.length-1的时候
r+1 = t.length
t[r+1]的话当然数组越界...
[解决办法]
应该是数组越界的问题吧，不清楚........
