UVA 164 Solution- String Computer

/*  Using Edit_Distance Algorithm */

#include<iostream>
#include<algorithm>
#include<string>
using namespace std;
string s1,s2;
int len1,len2,table[22][22];
void buildTable()
{
int i,j;
for(i=0;i<=len1;i++)
table[i][0]=i;
for(j=0;j<=len2;j++)
table[0][j]=j;
for(i=1;i<=len1;i++)
{
for(j=1;j<=len2;j++)
{
if(s1[i-1]==s2[j-1])
table[i][j]=table[i-1][j-1];
else
table[i][j]=min(table[i-1][j-1],min(table[i-1][j],table[i][j-1]))+1;
}
}
}
void result()
{
int i=len1,j=len2;
while(i || j)
{
if(s1[i-1]==s2[j-1])
{
i--;
j--;
continue;
}
if(j>0 && (table[i][j]==table[i][j-1]+1))
{
cout<<"I"<<s2[j-1];
if(i<=8)
cout<<"0";
cout<<i+1;
j--;
}
else if(i>0 && j>0 && (table[i][j]==table[i-1][j-1]+1))
{
cout<<"C"<<s2[j-1];
if(i<=9)
cout<<"0";
cout<<i;
i--;
j--;
}
else if(i>0)
{
cout<<"D"<<s1[i-1];
if(i<=9)
cout<<"0";
cout<<i;
i--;
}
}
cout<<"E"<<endl;
}
int main()
{
freopen("in.txt","r",stdin);
freopen("out.txt","w",stdout);
while(cin>>s1)
{
if(s1[0]=='#')
break;
cin>>s2;
len1=s1.size();
len2=s2.size();
buildTable();
result();
}
return 0;
}