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Levenshtein distance
import java.io.*;
import java.util.*;
public class levenshtein_distance{
public static HashSet[]h=new HashSet[25];
public static Stack<String>st=new Stack<String>();
public static HashSet<String>fnl=new HashSet<String>();
public static void main(String args[]) throws Exception{
long aa=System.currentTimeMillis();
InputReader sc=new InputReader(new FileInputStream("in.txt"));
int i,j;
for(i=0;i<25;i++) h[i]=new HashSet<String>();
String a="";
for(;!sc.isExhausted();){
a=sc.readLine();
h[a.length()].add(a);
}
String tof="hello";
st.add(tof);
while(!st.isEmpty()){
a=st.pop();
fnl.add(a);
addwords(a);
}
System.out.println(fnl.size()-1);
System.out.println((System.currentTimeMillis()-aa)+"ms");
}
public static void addwords(String wrd){
int i,len=wrd.length();
char z;
StringBuffer sb;
String b="";
for(i=0;i<len;i++){
sb=new StringBuffer(wrd);
sb=sb.deleteCharAt(i);b=sb.toString();
if(h[len-1].contains(b)){
st.add(b);h[len-1].remove(b);
}
}
for(i=0;i<=len;i++){
for(z='a';z<='z';z++){
sb=new StringBuffer(wrd);
sb=sb.insert(i,z);
b=sb.toString();
if(h[len+1].contains(b)){
st.add(b);h[len+1].remove(b);
}
}
}
for(i=0;i<len;i++){
for(z='a';z<='z';z++){
sb=new StringBuffer(wrd);
sb.setCharAt(i,z);
b=sb.toString();
if(h[len].contains(b)){
st.add(b);h[len].remove(b);
}
}
}
}
}
class InputReader {
private boolean finished = false;
private InputStream stream;
private byte[] buf = new byte[1024];
private int curChar;
private int numChars;
public InputReader(InputStream stream) {
this.stream = stream;
}
public int read() {
if (numChars == -1)
throw new InputMismatchException();
if (curChar >= numChars) {
curChar = 0;
try {
numChars = stream.read(buf);
} catch (IOException e) {
throw new InputMismatchException();
}
if (numChars <= 0)
return -1;
}
return buf[curChar++];
}
public int peek() {
if (numChars == -1)
return -1;
if (curChar >= numChars) {
curChar = 0;
try {
numChars = stream.read(buf);
} catch (IOException e) {
return -1;
}
if (numChars <= 0)
return -1;
}
return buf[curChar];
}
public int readInt() {
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
int res = 0;
do {
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
} while (!isSpaceChar(c));
return res * sgn;
}
public long readLong() {
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
long res = 0;
do {
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
} while (!isSpaceChar(c));
return res * sgn;
}
public String readString() {
int c = read();
while (isSpaceChar(c))
c = read();
StringBuffer res = new StringBuffer();
do {
res.appendCodePoint(c);
c = read();
} while (!isSpaceChar(c));
return res.toString();
}
public static boolean isSpaceChar(int c) {
return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
}
private String readLine0() {
StringBuffer buf = new StringBuffer();
int c = read();
while (c != '\n' && c != -1) {
if (c != '\r')
buf.appendCodePoint(c);
c = read();
}
return buf.toString();
}
public String readLine() {
String s = readLine0();
while (s.trim().length() == 0)
s = readLine0();
return s;
}
public String readLine(boolean ignoreEmptyLines) {
if (ignoreEmptyLines)
return readLine();
else
return readLine0();
}
public char readCharacter() {
int c = read();
while (isSpaceChar(c))
c = read();
return (char) c;
}
public double readDouble() {
int c = read();
while (isSpaceChar(c))
c = read();
int sgn = 1;
if (c == '-') {
sgn = -1;
c = read();
}
double res = 0;
while (!isSpaceChar(c) && c != '.') {
if (c == 'e' || c == 'E')
return res * Math.pow(10, readInt());
if (c < '0' || c > '9')
throw new InputMismatchException();
res *= 10;
res += c - '0';
c = read();
}
if (c == '.') {
c = read();
double m = 1;
while (!isSpaceChar(c)) {
if (c == 'e' || c == 'E')
return res * Math.pow(10, readInt());
if (c < '0' || c > '9')
throw new InputMismatchException();
m /= 10;
res += (c - '0') * m;
c = read();
}
}
return res * sgn;
}
public boolean isExhausted() {
int value;
while (isSpaceChar(value = peek()) && value != -1)
read();
return value == -1;
}
public String next() {
return readString();
}
}
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