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omeli [17]
3 years ago
15

Prove that any amount of postage greater than or equal to 64 cents can be obtained using only 5-cent and 17-cent stamps?

Computers and Technology
1 answer:
elixir [45]3 years ago
6 0
Let P(n) be "a postage of n cents can be formed using 5-cent and 17-cent stamps if n is greater than 63".Basis step: P(64) is true since 64 cents postage can be formed with one 5-cent and one 17-cent stamp.Inductive step: Assume that P(n) is true, that is, postage of n cents can be formed using 5-cent and 17-cent stamps. We will show how to form postage of n + 1 cents. By the inductive hypothesis postage of n cents can be formed using 5-cent and 17-cent stamps. If this included a 17-cent stamp, replace this 17-cent stamp with two 5-cent stamps to obtain n + 1 cents postage. Otherwise, only 5-cent stamps were used and n  65. Hence there are at least three 5-cent stamps forming n cents. Remove three of these 5-cent stamps and replace them with two 17-cent stamps to obtain n + 1 cents postage.Hence P(n + 1) is true.
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Prompt the user to input an integer, a double, a character, and a string, storing each into separate variables. Then, output tho
katen-ka-za [31]

Answer:

import java.util.Scanner;

public class BasicInput {

   public static void main(String[] args) {

       //Create an object of the Scanner class

       Scanner scnr = new Scanner(System.in);

       

       //Define int and double variables

       int userInt;

       double userDouble;

       

       //Define char and string variables similarly

       char userChar;

       String userString;

       

       //Prompt the user to enter an integer

      System.out.println("Enter integer:");

       //Store the input in the integer variable

       userInt = scnr.nextInt();

       

       //Prompt the user to enter a double

        System.out.println("Enter double:");

       //Store the input in the double variable

      userDouble = scnr.nextDouble();

       

       //Prompt the user to enter a char

        System.out.println("Enter char:");

       //Store the input in the char variable

      userChar = scnr.next().charAt(0);

       

       //Prompt the user to enter a string

        System.out.println("Enter String:");

       //Store the input in the string variable

      userString = scnr.next();

       

       //Output the four values on a single line

       //separated by a space

       System.out.println(userInt + " " + userDouble + " " + userChar + " " + userString);

       

   }

   

}

Sample Output:

Enter integer:

>>12

Enter double:

>>23

Enter char:

>>s

Enter String:

>>asdasd

12 23.0 s asdasd

Explanation:

The code above has been written in Java. It contains comments explaining every part of the code. Please go through the comments.

5 0
3 years ago
Write a function called count_occurrences that takes two strings. The second string should only be one character long. The funct
iVinArrow [24]

Answer:

Here is the Python function:

def count_occurrences (string1 , string2):  # method that takes two strings as parameter and returns how many times second string occurs in first

   count = 0  #counts number of occurrence of string2 in string1

   for word in string1:  #iterates through each word of the string1

       for character in word:  #iterates through each character of each word in string1

           if character == string2:  # checks if the character in string1 is equal to the character of string2

               count = count + 1  #adds 1 to the count of string2 in string1

   return count  #returns number of times the string2 occurs in string1

#in order to check the working of the function add the following lines to the code:    

first_str = input("Enter the first string: ")  #prompts user to enter first string

second_str = input("Enter the second string (one character long): ") #prompts user to enter second string which should be one character long

occurrence = count_occurrences(first_str,second_str)  #calls count_occurrences method by passing both strings to it

print(second_str,"occurs",occurrence,"times in",first_str) #prints how many times the second_str occurs in the first_str on output screen

Explanation:

The program is well explained in the comments added to each statement of the above code. I will explain the program with an example:

Suppose

string1 = "hello world"

string2 = 'l'

So the method count_occurrences() should return how many times l occurs in hello world.

count is used to count the number of occurrences of l in hello world. It is initialized to 0.

The first loop iterates through each word of string1. The first word of string1 is "hello"

The second loop iterates through each character/letter of each word. So the first letter of "hello" word is 'h'.

The if condition if character == string2: checks if the character is equal to string2 i.e. l.

character = "h"

string2 = "l"

The are not equal so the program moves to the next character of word hello which is e. The if condition again evaluates to false because e is not equal to l. So the program moves to the next character of word hello which is l.

This time the if condition evaluates to true because

character = "l"

string2 = "l"

character == string2

l == l

So the if part is executed which has the following statement:

count = count + 1

So the count is added to 1. count was 0 previously. Now

count = 1

Next the program moves to the next character of word hello which is l. This time the if condition evaluates to true because the character l matches with string2. So count is again incremented to 1. count = 2.

Next the program moves to the next character of word hello which is o. The if condition evaluates to false as o does not match with string2 i.e. l. So the count remains 2.

Next the first loop moves to the next word of the string1 = "world". The inner (second) for loop iterates through each character of "world" from "w" to "d" and checks if any character is equal to string2. Only one character is equal to string2 in "world". So count is incremented to 1. Hence count = 3

After the loop ends the statement return count returns the number of times string2 occurs in the string1. So the output is:

l occurs 3 times in hello world  

8 0
3 years ago
Pseudoscience is
madreJ [45]
C is going to be your answer 
6 0
3 years ago
Read 2 more answers
Namecoin is an alternative blockchain technology that is used to implement decentralized version of Routing Banking System.A. Tr
vova2212 [387]

Answer:

False

Explanation:

Namecoin is a type of crypto currency which was originally pronged from Bitcoin software. It is coded in the fashion of Bitcoin with the same algorithm as well. Hence it is not a blockchain technology that is used to implement decentralized version of Routing Banking System. Namecoin can store data within its own blockchain transaction database.

4 0
3 years ago
What is online school like 3 sentences
lara [203]

Answer:

its okay. i mean like you have to do a bunch off stuff. andsomtimes it gets a little boring.

Explanation:

i am doing online school.

3 0
3 years ago
Read 2 more answers
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