Problem 5

This program finds the smallest and largest integers in a list.  Enter values, one per line, using a 0 to signal the end of the list
?32
?2
?4
?5
?45
?1
?0
Smallest value was 1
Largest value was 45

/*
 * File: FindRange.java
 * --------------------
 * This program is a stub for the FindRange problem, which finds the
 * smallest and largest values in a list of integers.
 */

import acm.program.*;
import java.io.Console;

public class FindRange extends ConsoleProgram {

	public void run() {
		int readInValue=sential;
		println("This program finds the smallest and largest integers in a list.  Enter values, one per line, using a "+sential+" to signal the end of the list");
		do 
		{
			readInValue = readInt("?");
			if (readInValue != sential)
			{
				if (readInValue > largestValue)
					largestValue = readInValue;
				if (readInValue < smallestValue || smallestValue == sential)
					smallestValue = readInValue;
			}
		} while (readInValue != sential);
		if (largestValue == smallestValue && largestValue == sential)
		{
			println("No values inputted");
		}
		else
		{
			println("Smallest value was "+ smallestValue);
			println("Largest value was " + largestValue);
		}
	}

	private int largestValue = 0, smallestValue = 0;
	private static final int sential = 0;
}

4 thoughts on “Problem 5”

1. import acm.program.*;
   
   public class FindRange extends ConsoleProgram {
   	private static final int SENTINEL=0;
   
   	public void run() {
   		// Initialisation of variables
   		int smallNumber=0;
   		int bigNumber=0;
   		int x=0;
   		int read;
   
   		// While Loop with break for SENTINEL
   		while(true){
   			read=readInt("Enter number ");
   
   			// Make the 1st value same for both only once
   			while(x==0){
   				smallNumber=read;
   				bigNumber=read;
   				x=1;
   			}
   
   			// Conditions and Checks
   			if(read==SENTINEL){break;}
   			else if (read  bigNumber){bigNumber=read;}
   		}
   		// Check for final Println
   		if(bigNumber!=0 && smallNumber!=0){
   			println("small number "+smallNumber+" big number "+bigNumber);
   		}else{println("You have not entered any value");}
   	}
   }
   

2. The sentinel should not be included in calculating the largest or smallest, it simply marks the end of the list.

   However, if all the integers are negative, the program states that the largest integer is 0, which is wrong.

3. /*
    * File: FindRange.java
    * Name: 
    * Section Leader: 
    * --------------------
    * This file is the starter file for the FindRange problem.
    */
   
   import acm.program.*;
   
   public class FindRange extends ConsoleProgram {
   	
   	private static final int SENTINEL = 0;
   	
   	public void run() {
   		
   		//initializes variables
   		int bigNumber = -2147483648;
   		int smallNumber  = 2147483647;
   		int input;
   		boolean firstZero = false;
   		
   		println("This program find the smallest and largest integers in a list. Enter a 0 to signal the end of the list.");
   		
   		while(true){
   			//takes the value the user enters and stores it in the variable input
   			input = readInt("?");
   			
   			//if the input is 0 and the initial variables have not changed, indicating that 0 was the first value entered, then we set the variable firstZero (which indicates the first value entered was zero) to true and break from the loop.
   			if(input == SENTINEL && bigNumber == -2147483648 && smallNumber  == 2147483647){
   				firstZero = true;
   				break;
   			}
   			
   			//if the input is zero, break from the loop
   			if(input == SENTINEL){break;}
   			
   			//if the input is bigger than the value of bigNumber, then store it in bigNumber
   			if(input > bigNumber){			
   				bigNumber = input;
   			} 
   			
   			//if the input is smaller than the value of smallNumber, then store it in smallNumber
   			//the first number entered will be stored in both variables, with two exceptions (-2147483648 & 2147483647)
   			if (input < smallNumber){
   				smallNumber = input;
   			}	
   		}
   		
   		//if the first value entered was zero, display this text
   		if(firstZero == true){
   			println("You have not entered any numbers.");
   		//otherwise, display this text	
   		} else {
   		println("small:" + smallNumber + "big:" + bigNumber);
   		}
   	}
   }
   

   //note: this program works for ALL cases except for if the user ONLY enters 2147483647 and -2147483648. it will work if they enter one of them (alone or with other integers).

4. /*
    * File: FindRange.java
    * Name: 
    * Section Leader: 
    * --------------------
    * This file is the starter file for the FindRange problem.
    */
   
   import acm.program.*;
   
   public class FindRange extends ConsoleProgram {
   	public void run() {
   		println("This program finds the largest number");
   		println("Please type the number you want, one per line,using " + SENTINEL +".");
   		
   		int value = readInt("? ");
   		int biggest = value;
   		int smallest = value;
   		while (true) {
   			int value2 = readInt("? ");
   			if (value2 == SENTINEL) break;
   			if (value2 > biggest) {
   				biggest = value2;
   			}
   			if (value2 < smallest) {
   				smallest = value2;
   			}
   		}
   		println("Biggest:" + biggest +".");
   		println("Smallest:" + smallest +".");
   	}
   	private static final int SENTINEL = 0;
   }