Question

Using switch statement, write a menu-driven program for the following : 

(i) To find and display the sum of the series given below :
S = x¹ -x² + x² – x⁴ + x⁵ – x²⁰ 
(where x = 2)
(ii) To display the following series :
1 11 111 1111 11111
For an incorrect option, an appropriate error message should be displayed.

Answer 1

import java.io.*;
class SwitchStatement {
public static void main(String argsQ) throws IOException {
InputStreamReader reader = new InputStreamReader(System.in);
BufferedReader input = new BufferedReader(reader);
System.out.println(“l-Sum of Series:”);
System.out.println(“2-Display Special Series:”);
System.out.println(“Enter your choice:”);
String n1 = input.readLine( );
int ch = Integer.parselnt(nl);
System.out.println(“Enter Number of Terms
String t = input.readLine();
int n = Integer.parselnt(t);
switch (ch) {
case 1:
int sign = -1;
double term = 0;
double sum = 0;
int x = 2;
System.out.println(“Value of x: ” +x);
System.out.println(“Number of terms: ” +n);
sum + = x; // First term added here,
for (int i = 2; i < = n; i+ +){
term = sign * Math.pow(x,i);
sum + = term;
sign *= -1;
}
System.out.println(“Sum of Series +sum);
break;
case 2 :
int num;
System.out.println(“Enter the number of terms: ”);
String tm = input.readLine(); .
num = Integer.parselnt(tm);
int s = 0, c;
for (c = 1; c < = num; c+ +){
s = s * 10 + 1;
System.out.print(s + ” “);
}
break;
}
}
}