Practice-Problems

These are some simple practice problem related to java. The Questions solved are given below:

Assignment 1

1. Write a JAVA program to find the multiplication of given 4 numbers. Also find their geometric mean.
2. Write a JAVA program which reads the value of the height and radius of the base of a cylinder and calculates the Volume of that cylinder.


3. Given as input a floating (real) number of centimeters, print out the equivalent number of feet (integer) and inches (floating, 1 decimal), with the inches given to an accuracy of one decimal place.


4. Given as input an integer number of seconds, print as output the equivalent time in hours, minutes and seconds. Recommended output format is something like 7322 seconds is equivalent to 2 hours 2 minutes 2 seconds.


5. Write a JAVA program to multiply two numbers without using * operator.


6. Write a JAVA program to find the roots of the quadratic equation and display a message that roots are equal or distinct or real or complex.


7. Write a JAVA program to find whether given integer n is a power of 2 or not. Also write a separate/same program to generate a first 50 power of 2 numbers.


8. Write a JAVA program to reverse a given number of 5 digits.


9. Write a JAVA program find the median of n numbers given by user.


10. Write a JAVA program to find the maximum of three numbers using ternary operator.


11. Evaluate the following expressions:
    (i) x = 2 % 2 + 2 * 2 - 2 / 2;
    (ii) Given a=4, b=5 and c=6;
    Find ((a < b) || (b > c) && (a > b) || (!(a > c)))
    (iii) i=8, j=5, x=0.005, y=-0.01
    Find 5* ((i / 7) + ( j *(i - 3))%(x + y - 2 + i))
    (iv) Given x=10 ,Find y=--x * x--
    (v) y=(t=6, 7*t+2)
    


12. Write a JAVA program which reads two numbers x and y, then find the GCD of x and y.


13. Write a JAVA program to find the sum of integers between 50 and 100, which are divisible by 7.


14. Write a JAVA program to find the factorial of number using (i) for loop (ii) while loop (iii) do loop

Assignment 2

1. Write a JAVA program which asks the user to supply an alphabet in upper case from the key board. Then convert the alphabet in lower case.


2. Write a JAVA program to display the names of the Months of the year, depending upon the number entered by the user using:
   (i) if – else
   (ii) switch – case


3. Read a positive integer value, and compute the following sequence: If the number is even, halve it; if it's odd, multiply by 3 and add 1. Repeat this process until the value is 1, printing out each value. Finally print out how many of these operations you performed. Write a JAVA Program.


4. Write a JAVA program to find the sum of the following series using (a) for loop (b) while loop and (c) do-while loop
   I. Sum = 1+ 5 +10 +15 + ....+ n
   II. Sum = 1- 1/1!+ 2/2! - 3/3! + 4/4!-....
   III. Sum = x - x³/3! + x⁵/5!-......-xⁿ/n!
   IV. Sum = 1²+2²+3²+4²+5²+.....+n²
   V. Sum = 1³-3³+5³-....n³
   


5. Write a JAVA program to simulate a calculator where the user enters two integer numbers and an operator (+, -, *, /, %). The program then carries out the specified operation and displays the result. Write using if statement as well as switch statement.


6. Write a JAVA program to display the table of a given number.


7. Write a JAVA program to check for palindromes for Integers as well as string using( For example 1221, 57866875 and avon sees nova are some palindromes): (i) if – else (ii) switch – case


8. Write a JAVA program to find the maximum and minimum of n numbers using:

   (a) for loop (b) while loop and (c) do-while loop



9. Write a JAVA program to check if given two numbers are relatively prime or not.


10. Write a JAVA program to find the perfect numbers between 1 to 100000. m is a perfect number if σ(m) = 2m , that is if m is the sum of all its positive divisors other than itself.
    σ (m) - sum of the positive divisors of m. For example σ (12) = 1+ 2 + 3 + 4 + 6 +12 = 28 where 1, 2, 3, 4, 6 and 12 are the positive divisors of 12. For example 28 is a perfect number σ (28) = 1 + 2 + 4 + 7 + 14 + 28 = 56


11. Write a JAVA program to generate Hemachandra series, 1, 2, 3, 5, 8, 13, 21...

Assignment 3

1. Ten numbers are entered from the keyboard into an array. The number to be searched is entered through the keyboard by the user. Write a program to find if the number to be searched is present in the array and if it is present, display the number of times it appears in the array.


2. Ten numbers are entered from the keyboard into an array. Write a program to find out how many of them are positive, how many are negative, how many are even and how many are odd.


3. Write a program to copy the contents of one array into another in the reverse order. The program should take double type values from the keyboard.


4. WAP for 5 × 5 matrix (a) entered through the keyboard (b) initialized in the program and stored in a 2-dimensional array mat[5][5]. Write a program to obtain the Determinant values of this matrix


5. Given two matrices A and B find its product using JAVA where A and B are Cartan matrices. A Cartan matrix is a square integer matrix who elements ( A_i,j) satisfy the following conditions.
   • A_i,j is an integer, one of belongs to {-3, -2, -1, 0, 2}.
   • A_i,j = 2 the diagonal entries are all 2.
   • A_i,j≤0 off of the diagonal.
   • A_i,j =0 iff A_i,j =0.
   More about Cartan matrix can be found in http://mathworld.wolfram.com/CartanMatrix.html


6. WAP to check whether given matrix is Upper Triangular or not.


7. WAP to find the maximum element of a given matrix.


8. WAP to find the non overlapping sub-matrix of the given matrix of given order. If the given matrix is A and order of sub-matrix is 2 then
   


9. Write and test the function that rotate 90 and 180 degrees clockwise a two dimensional square array of integers.