Solved 2019 Practical Paper ISC Computer Science — Question 3
Back to all questionsQuestion 3
Write a program to accept a sentence which may be terminated by either ‘.’, ‘?’ or ‘!’ only. The words are to be separated by a single blank space and are in uppercase.
Perform the following tasks:
(a) Check for the validity of the accepted sentence.
(b) Convert the non-palindrome words of the sentence into palindrome words by concatenating the word by its reverse (excluding the last character).
Example:
The reverse of the word HELP would be LEH (omitting the last alphabet) and by concatenating both, the new palindrome word is HELPLEH. Thus, the word HELP becomes HELPLEH.
Note: The words which end with repeated alphabets, for example ABB would become ABBA and not ABBBA and XAZZZ becomes XAZZZAX.
[Palindrome word: Spells same from either side. Example: DAD, MADAM etc.]
(c) Display the original sentence along with the converted sentence.
Test your program for the following data and some random data:
Example 1
INPUT:
THE BIRD IS FLYING.
OUTPUT:
THE BIRD IS FLYING.
THEHT BIRDRIB ISI FLYINGNIYLF
Example 2
INPUT:
IS THE WATER LEVEL RISING?
OUTPUT:
IS THE WATER LEVEL RISING?
ISI THEHT WATERETAW LEVEL RISINGNISIR
Example 3
INPUT:
THIS MOBILE APP LOOKS FINE.
OUTPUT:
THIS MOBILE APP LOOKS FINE.
THISIHT MOBILELIBOM APPA LOOKSKOOL FINENIF
Example 3
INPUT:
YOU MUST BE CRAZY#
OUTPUT:
INVALID INPUT
Solution
import java.util.*;
public class Palindrome
{
public static boolean isPalindrome(String word) {
boolean palin = true;
int len = word.length();
for (int i = 0; i <= len / 2; i++) {
if (word.charAt(i) != word.charAt(len - 1 - i)) {
palin = false;
break;
}
}
return palin;
}
public static String makePalindrome(String word) {
int len = word.length();
char lastChar = word.charAt(len - 1);
int i = len - 1;
while (word.charAt(i) == lastChar) {
i--;
}
StringBuffer sb = new StringBuffer(word);
for (int j = i; j >= 0; j--) {
sb.append(word.charAt(j));
}
return sb.toString();
}
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.println("ENTER THE SENTENCE:");
String ipStr = in.nextLine().trim().toUpperCase();
int len = ipStr.length();
char lastChar = ipStr.charAt(len - 1);
if (lastChar != '.'
&& lastChar != '?'
&& lastChar != '!') {
System.out.println("INVALID INPUT");
return;
}
String str = ipStr.substring(0, len - 1);
StringTokenizer st = new StringTokenizer(str);
StringBuffer sb = new StringBuffer();
while (st.hasMoreTokens()) {
String word = st.nextToken();
boolean isPalinWord = isPalindrome(word);
if (isPalinWord) {
sb.append(word);
}
else {
String palinWord = makePalindrome(word);
sb.append(palinWord);
}
sb.append(" ");
}
String convertedStr = sb.toString().trim();
System.out.println();
System.out.println(ipStr);
System.out.println(convertedStr);
}
}Output
import
java.util.*
;
public
class
Palindrome
{
public
static
boolean
isPalindrome
(
String
word
) {
boolean
palin
=
true
;
int
len
=
word
.
length();
for
(
int
i
=
0
; i
<=
len
/
2
; i
++
) {
if
(word
.
charAt(i)
!=
word
.
charAt(len
-
1
-
i)) {
palin
=
false
;
break
;
}
}
return
palin;
}
public
static
String
makePalindrome
(
String
word
) {
int
len
=
word
.
length();
char
lastChar
=
word
.
charAt(len
-
1
);
int
i
=
len
-
1
;
while
(word
.
charAt(i)
==
lastChar) {
i
--
;
}
StringBuffer
sb
=
new
StringBuffer
(word);
for
(
int
j
=
i; j
>=
0
; j
--
) {
sb
.
append(word
.
charAt(j));
}
return
sb
.
toString();
}
public
static
void
main
(
String
args
[]) {
Scanner
in
=
new
Scanner
(
System
.
in);
System
.
out
.
println(
"
ENTER THE SENTENCE:
"
);
String
ipStr
=
in
.
nextLine()
.
trim()
.
toUpperCase();
int
len
=
ipStr
.
length();
char
lastChar
=
ipStr
.
charAt(len
-
1
);
if
(lastChar
!=
'
.
'
&&
lastChar
!=
'
?
'
&&
lastChar
!=
'
!
'
) {
System
.
out
.
println(
"
INVALID INPUT
"
);
return
;
}
String
str
=
ipStr
.
substring(
0
, len
-
1
);
StringTokenizer
st
=
new
StringTokenizer
(str);
StringBuffer
sb
=
new
StringBuffer
();
while
(st
.
hasMoreTokens()) {
String
word
=
st
.
nextToken();
boolean
isPalinWord
=
isPalindrome(word);
if
(isPalinWord) {
sb
.
append(word);
}
else
{
String
palinWord
=
makePalindrome(word);
sb
.
append(palinWord);
}
sb
.
append(
"
"
);
}
String
convertedStr
=
sb
.
toString()
.
trim();
System
.
out
.
println();
System
.
out
.
println(ipStr);
System
.
out
.
println(convertedStr);
}
}
Output