/*
Mohamed Anis MEKKI - 2003 (c)
*/
public class code
{
symbol symbols[];
String codes[];
int length;
public code(source s)
{
this.length = s.length;
this.symbols = s.symbols;
this.codes = new String[1000];
int i=0;
while (i < s.length)
{
(this.codes)[i] = "";
i++;
}
}
public double lmoy()
{
double result = 0.0;
int i = 0;
while ( (i < symbols.length) && (symbols[i] != null) )
{
result = result + ((symbols[i].prob)*(codes[i].length()));
i++;
}
return(result);
}
public double lmin()
{
double result = 0.0;
int i = 0;
while ( (i < symbols.length) && (symbols[i] != null) )
{
result = result - ((symbols[i].prob)*Math.log((symbols[i].prob)));
i++;
}
result = result / Math.log(2);
return(result);
}
public double rendement()
{
return(lmin()/lmoy());
}
public void show()
{
int i=0;
while (i < this.length)
{
((this.symbols)[i]).show();
System.out.println("Code : "+(this.codes)[i]);
i++;
}
}
public void encode(String s,int c)
{
int i=0;
int j=0;
s=s+"-";
int l = s.length()/2;
String str[] = new String[l];
while ( s.length() > 0 )
{
str[j]="";
while ( s.charAt(i) != '-' )
{
str[j] = str[j]+s.charAt(i);
i++;
}
s = s.substring(i+1);
i=0;
j++;
}
j=0;
while ( j < str.length )
{
i=0;
while ( i < this.length )
{
if ( (((this.symbols)[i]).symb).equals(str[j]) )
{
this.codes[i]=c+this.codes[i];
}
i++;
}
j++;
}
}
public tree hauffman()
{
int i= this.length;
int j=0;
tree tree_result[] = new tree[i];
tree result = new tree(null,null,null);
tree permut = new tree(null,null,null);
while ( j < i )
{
tree_result[j] = new tree((this.symbols)[j],null,null);
j++;
}
while ( i > 1 )
{
this.encode(((tree_result[i-1]).root).symb,1);
this.encode(((tree_result[i-2]).root).symb,0);
permut = tree_result[i-2];
tree_result[i-2] = new tree((permut.root).add((tree_result[i-1]).root),tree_result[i-1],permut);
i--;
tree_result = tree.classify_tree_up(tree_result,i);
}
result = tree_result[0];
return(result);
}
public static void main(String args[])
{
source M = new source();
source M2 = new source();
source M3 = new source();
source M4 = new source();
symbol a1 = new symbol("A1",0.8);
symbol a2 = new symbol("A2",0.2);
symbol a3 = new symbol("A3",0.1);
//symbol a3 = new symbol("c",0.1);
M.add_symbol(a1);
M.add_symbol(a2);
//M.add_symbol(a3);
M2 = M.extend2();
M2.classify_up();
M3 = M2.extend2();
M3.classify_up();
M4 = M3.extend2();
M4.classify_up();
code c = new code(M4);
tree hauffman_tree = c.hauffman();
hauffman_tree.show();
c.show();
System.out.println(" lmin : "+c.lmin());
System.out.println(" lmoy : "+c.lmoy());
System.out.println("rendement : "+c.rendement());
}
}
