Write a Program in Java to input a number and check whether it is a Pronic Number or Heteromecic Number or not.
Pronic Number : A pronic number, oblong number, rectangular number or heteromecic number, is a number which is the product of two consecutive integers, that is, n (n + 1).
The first few pronic numbers are:
0, 2, 6, 12, 20, 30, 42, 56, 72, 90, 110, 132, 156, 182, 210, 240, 272, 306, 342, 380, 420, 462 … etc.o edit text
0, 2, 6, 12, 20, 30, 42, 56, 72, 90, 110, 132, 156, 182, 210, 240, 272, 306, 342, 380, 420, 462 … etc.o edit text
import java.util.*;
class PronicNumber
{
public static void main(String args[])
{
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number : ");
int n = sc.nextInt();
int k = (int)(Math.sqrt(n));
if(k*(k+1)==n)
System.out.println(n+" is a Pronic Number.");
else
System.out.println(n+" is not a Pronic Number.");
}
}
Write a program to input a word from the user and remove the duplicate characters present in it.
Example:
INPUT – abcabcabc
OUTPUT – abc
OUTPUT – abc
INPUT – javaforschool
OUTPUT – javforschl
OUTPUT – javforschl
INPUT – Mississippi
OUTPUT – Misp
OUTPUT – Misp
import java.io.*;
class RemoveDupChar
{
public static void main(String args[])throws IOException
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter any word : ");
String s = br.readLine();
int l = s.length();
char ch;
String ans="";
for(int i=0; i<l; i++)
{
ch = s.charAt(i);
if(ch!=' ')
ans = ans + ch;
s = s.replace(ch,' '); //Replacing all occurrence of the current character by a space
}
System.out.println("Word after removing duplicate characters : " + ans);
}
}
Write a program to input a word from the user and remove the consecutive repeated characters by replacing the sequence of repeated characters by its single occurrence.
Example:
INPUT – Jaaavvvvvvvvaaaaaaaaaaa
OUTPUT – Java
OUTPUT – Java
INPUT – Heeeiiiissggoiinggg
OUTPUT – Heisgoing
OUTPUT – Heisgoing
import java.io.*;
class RemoveRepChar
{
public static void main(String args[])throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter any word: ");
String s = br.readLine();
s = s + " ";
int l=s.length();
String ans="";
char ch1,ch2;
for(int i=0; i<l-1; i++)
{
ch1=s.charAt(i);
ch2=s.charAt(i+1);
// Adding the first extracted character to the result if the current and the next characters are different
if(ch1!=ch2)
{
ans = ans + ch1;
}
}
ns=ns+s.charAt(l-1);
System.out.println("Word after removing repeated characters = "+ans);
}
}
Question
Write a program to enter an integer and check whether it is a Harshad Number or not.
[Harshad number or Niven number is an integer which is divisible by sum of its digits. Example-18]
public class Harshad_no_459
{
public static void main(int n)
{
int a=n,s=0;
while(a>0)
{
int d=a%10;
s=s+d;
a=a/10;
}
if(n%s==0)
{
System.out.println("Harshad No.");
}
else
{
System.out.println("Not a Harshad No.");
}
}
}
Question
54321+4321+321+21+1
public class sum_series
{
public static void main()
{
int n=54321,s=0;
for(int x=10000;x>0;x=x/10)
{
s=s+n;
n=n%x;
}
System.out.println("Sum="+s);
}
}
1. Pell_series
Write a program to display first 20 numbers of the Pell series.
1,2, 5, 12, 29, 70, ……
[Pell series is such a series which starts from 1 and 2 and subsequent numbers are the sum of twice the previous number and the number previous to the previous number.
Ex. 5=2*2+1, 12=5*2+2 and so on]
package loop;
public class pell_series_429
{
public static void main()
{
int a=1,b=2;
System.out.println(a);
System.out.println(b);
for(int x=1;x<=18;x++)
{
int c=b*2+a;
System.out.println(c);
a=b;
b=c;
}
}
}
2. sum_series
9+99+8+89+7+79+……….+0+9
package loop;
public class sum_series_430
{
public static void main()
{
int s=0;
for(int x=9;x>=0;x--)
{
s=s+x+(x*10+9);
}
System.out.println(s);
}
}
(Stewart)
- Write a program to accept a number and check whether it is palprime or not.
public class PalPrime{public static void main(int n){int a=n,r=0;while(a>0){int d=a%10;r=r*10+d;a=a/10;}int c=0;for(int f=1;f<=n;f++){if(n%f==0){c++;}}if(c==2 && r==n){System.out.println("Palprime");}else{System.out.println("not Palprime");}}}/*2. Write a program to input 2 integers n and p, find and display n raised to power p. Do not use Math.pow.*/package stewart;public class power_calc{public static void main(int n,int p){int v=1;while(p>0){v=v*n;p--;}System.out.println(v);}}/*3. 1+a/3+2+a/5+3+a/7…..upto n terms*/package stewart;public class sum_series1{public static void main(int n,int a){double s=0.0;for(int x=1;x<=n;x++){s=s+x+a/(x*2+1);}System.out.println(s);}}/*4. Write a program to evaluate a function fx=(x2+1.5x+5)/(x-3) where x is ranging from -10 to +10.*/package stewart;public class equation{public static void main(){for(int x=-10;x<=10;x++){double fx=(x*x+1.5*x+5)/(x-3);System.out.println(x+" "+fx);}}}/*5. 1/2-2/4+3/6-4/8……upto n terms*/package stewart;public class sum_series{public static void main(int n){double s=0.0;for(int a=1;a<=n;a++){if(a%2==0){s=s-(double)a/(a*2);}else{s=s+(double)a/(a*2);}}System.out.println(s);}}/*6. 1*1/5*2/10*3/15*……*5/25 */package stewart;public class sum_series_6{public static void main(){double p=1.0;for(int a=1;a<=5;a++){p=p*(double)a/(a*5);}System.out.println(p);}}/*7. 1/1-(1*2)/2+(1*2*3)/3-(1*2*3*4)/4……upto n terms*/package stewart;public class sum_series7{public static void main(int n){double s=0.0;for(int x=1;x<=n;x++){int p=1;for(int y=1;y<=x;y++){p=p*y;}if(x%2==0){s=s-(double)p/x;}else{s=s+(double)p/x;}}System.out.println("Sum="+s);}}/*8. Write a menu driven program to find the sum of the following series depending on the user choosing 1 or 2(i) 1/4+1/8+1/12…….upto n terms(ii) 1/1!-2/2!+3/3!.........upto n terms */package stewart;public class menu_8{public static void main(int n,int ch){switch(ch){case 1:double s=0.0;for(int a=1,b=4;a<=n;a++,b=b+4){s=s+1.0/b;}System.out.println("Sum="+s);break;case 2:double sum=0.0;for(int a=1;a<=n;a++){int k=a,f=1;while(k>0){f=f*k;k--;}if(a%2==0){sum=sum-(double)a/f;}else{sum=sum+(double)a/f;}}System.out.println("Sum="+sum);break;default:System.out.println("Invalid entry");}}}/* 9. Define a class menu to perform the following operations depending upon the user';s choice:a) find out the square root of the numberb) rounded down value of a numberc) rounded up value of a number*/package stewart;public class menu9{public static void main(double n,int ch){switch(ch){case 1:double s=Math.sqrt(n);System.out.println("Square Root="+s);break;case 2:double rd=Math.floor(n);System.out.println("Rounded down value="+rd);break;case 3:double ru=Math.ceil(n);System.out.println("Rounded up value="+ru);break;default:System.out.println("Invalid entry");}}}/*10. In an election,out of 1249 voters in a booth,only 869 voters chose theirfranchises correctly.If 5 candidates are contesting,write a program to find:i) number of valid and invalid votesii) percentage of valid votes received by each candidate*/package stewart;public class vote_10{public static void main(int a,int b,int c,int d,int e){int tv=1249,vv=869;int iv=tv-vv;double pa,pb,pc,pd,pe;pa=(double)a/vv*100;pb=(double)b/vv*100;pc=(double)c/vv*100;pd=(double)d/vv*100;pe=(double)e/vv*100;System.out.println(pa+" "+pb+" "+pc+" "+pd+" "+pe);}}/*11. Write a program to add two times given in hours and minutes. */package stewart;public class time_11{public static void main(int h1,int m1,int h2,int m2){int h=h1+h2;int m=m1+m2;if(m>60){m=m-60;h=h+1;}System.out.println("Sum="+h+" hours "+m+" minutes");}}/*12. Write a program to enter an integer and convert it from decimal to binary. */package stewart;public class decimal_binary_12{public static void main(int n){String b="";int a=n;while(a>0){int d=a%2;b=d+b;a=a/2;}System.out.println(b);}}/* 13. octal to decimal */package stewart;public class octal_to_decimal_13{public static void main(int octal){int a=octal,num=0,v=1;while(a>0){int d=a%10;num=num+d*v;v=v*8;a=a/10;}System.out.println(num);}}/* 14. binary to octal*/package stewart;public class binary_to_octal_14{public static void main(int n){int a=n,num=0,v=1;while(a>0)//loop to convert binary to decimal{int d=a%10;num=num+d*v;v=v*2;a=a/10;}String r="";a=num;while(a>0)//loop to convert decimal to octal{int d=a%8;r=d+r;a=a/8;}//int r=Integer.parseInt(r);System.out.println(r);}}/*15. octal to binary */package stewart;public class octal_to_binary_15{public static void main(int octal){int a=octal,num=0,v=1;while(a>0)//loop to convert octal to decimal{int d=a%10;num=num+d*v;v=v*8;a=a/10;}String b="";a=num;while(a>0)//loop to convert decimal to binary{int d=a%2;b=d+b;a=a/2;}System.out.println(b);}}/*16. write a program to enter an integer and convert it into fraction by placing product of all odd digits in the denominator and product of all even digits in the numerator. */package stewart;public class integer_to_fraction_16{public static void main(int n){int a=n,pe=1,po=1;while(a>0){int d=a%10;if(d%2==0){pe=pe*d;}else{po=po*d;}a=a/10;}double num=(double)pe/po;System.out.println(num);}}/*17. Write a program to enter a number and check whether it isdivisible by minimum by three prime numbers.*/package stewart;public class divisible_by_prime_17{public static void main(int n){int ctr=0;for(int m=1;m<=n;m++){int c=0;for(int f=1;f<=m;f++){if(m%f==0){c++;}}if(c==2){if(n%m==0){ctr++;}}}if(ctr>=3){System.out.println("div. by min. 3 prime nos.");}else{System.out.println("not div. by min. 3 prime nos.");}}