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finding larger number with recursion

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Join Date: Oct 2007

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anga08628

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finding larger number with recursion

Nov 5th, 2007

//Write a function: int max(int list[], int n) that recursively finds the largest integer between list[0] and list[n]. Assume at least one element in the list. Test it with a main program that takes as input an integer count followed by that many values. Output the original values followed by the maximum. Do not use a loop in max(). Output the value in the main program, not in the funcion.
//Sample input:
//5 50 30 90 20 80
//Sample output:
//Original list: 50 30 90 20 80
//Largest value: 90

 Help with Code Tags 
 cpp Syntax (Toggle Plain Text) 
# include <iostream>
using namespace std;
int max(int list[], int n)
int main ()
{
int list[30]
 
	cout << "please type in numbers:  ";
	cin.getline (list, 30, '\n');
	cout << "original list: " << list [] << endl;
	cout << "largest value: " << n << endl;
 
 
system ("pause");
return 0;
}
 
 
int max(int list[], int n)
{
# include <iostream>
using namespace std;
int max(int list[], int n)
int main ()
{
int list[30]
	
	cout << "please type in numbers:  ";
	cin.getline (list, 30, '\n');
	cout << "original list: " << list [] << endl;
	cout << "largest value: " << n << endl;

	
system ("pause");
return 0;
}


int max(int list[], int n)
{

//am not sure what to do next. I get the concept that i have to keep minmizing it, bit i so not know how to do that. please help!

Last edited by WaltP; Nov 5th, 2007 at 12:52 am. Reason: Added CODE tags -- you actually typed right over how to use them when you entered this post... And removed unecessary colors.

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WaltP

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Re: finding larger number with recursion

Nov 5th, 2007

Is there something about CODE tags you don't understand? If not, you can either ask or read those words on the back of the input box for information.

The project states "Test it with a main program that takes as input an integer count followed by that many values." Where did you read an integer count? Doesn't getline() read a string, not a list of integers? You need to use a loop to read (and output) your numbers.

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Salem

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Re: finding larger number with recursion

Nov 5th, 2007

Well the first question is, can you solve this problem using regular iteration?

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tracethepath tracethepath is offline

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Re: finding larger number with recursion

-1

Nov 5th, 2007

instead of line 9, you should use a for loop to get the values for the integer array list...

and as WaltP said you have not read an integer count...it should have been read before line 8...

line 10 too is incorrect...you dont display an integer array like that...you have to use the for loop there...

$With Regards...$

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tracethepath tracethepath is offline

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Re: finding larger number with recursion

Nov 5th, 2007

n again you have to call the function max between lines 10 and 11...or otherwise from where you will get the value for "n"??

$With Regards...$

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anga08628

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Re: finding larger number with recursion

Nov 5th, 2007

so is int list[] an array? and i would have to call every element of it?

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anga08628

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Re: finding larger number with recursion

Nov 6th, 2007

WHAT WOULD BE ANOTHER WAY I COULD WRITE THE LAST PART OF THIS FUNCTION?

//Write a function: int max(int list[], int n) that recursively finds the largest integer between list[0] and list[n]. Assume at least one element in the list. Test it with a main program that takes as input an integer count followed by that many values. Output the original values followed by the maximum. Do not use a loop in max(). Output the value in the main program, not in the funcion.
//Sample input:
//5 50 30 90 20 80
//Sample output:
//Original list: 50 30 90 20 80
//Largest value: 90

 Help with Code Tags 
 c++ Syntax (Toggle Plain Text) 
# include <iostream>
using namespace std;
int max(int[], int);
int main ()
{
	int list[40]; 
int number_size=0;
 
 
	cout << "how many numbers you want to input?  ";
	cin >> number_size;
	for(int i=0; i<number_size;i++)
		cin >> list[i];
	cout << "original list: " << endl;
	for(int i=0; i<number_size; i++);
		cout << list[i] << endl;
	cout << "largest value: " << max(list, number_size) << endl;
 
 
system ("pause");
return 0;
}
 
 
int max(int l[], int n)
{
 
 static int count=0; 
int maximum= l[count];
 
if (maximum<l[count])
maximum=l[count];
count++;
if (count==n)
return maximum;                               
return max(l,n);
}
# include <iostream>
using namespace std;
int max(int[], int);
int main ()
{
	int list[40]; 
int number_size=0;

	
	cout << "how many numbers you want to input?  ";
	cin >> number_size;
	for(int i=0; i<number_size;i++)
		cin >> list[i];
	cout << "original list: " << endl;
	for(int i=0; i<number_size; i++);
		cout << list[i] << endl;
	cout << "largest value: " << max(list, number_size) << endl;

	
system ("pause");
return 0;
}


int max(int l[], int n)
{

 static int count=0; 
int maximum= l[count];

if (maximum<l[count])
maximum=l[count];
count++;
if (count==n)
return maximum;                               
return max(l,n);
}

Last edited by Ancient Dragon; Nov 6th, 2007 at 8:57 am. Reason: replace color tags with code tags

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tracethepath tracethepath is offline

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Re: finding larger number with recursion

Nov 6th, 2007

line 15, you have declare i again...that is not correct...and you have placed a semi colon after for loop there...so line 16 will run just once and will not give the desired output...

and line 29 should not be there...instead it should be

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
 
static int maximum=l[0];
 
static int maximum=l[0];

otherwise as the function is called again and again maximum value will be initialised to present l[count]...and the maximum value till that point will be lost...

$With Regards...$

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payara111

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Re: finding larger number with recursion

-1

May 13th, 2009

•

Try It, I think it will solve your problem

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include<iostream.h>
#include<conio.h>
 
 
int find(int *a,int start,int end)
{
 
 
	if(start<end)
	{
 
		if(a[start]<a[end])
		{
 
		cout<<"1st Arrys condition"<<a[start]<<" "<<a[end]<<endl;
		return find(a,start+1,end);
 
		}
		else
		cout<<"2nd Arrys condition"<<a[start]<<" "<<a[end]<<endl;
		return find(a,start,end-1);
 
	}
	cout<<"Last= "<<a[end]<<endl;
}
 
void main()
{
clrscr();
 
const int size=8;
int arr[size]={7,6,13,12,2,9,5,99};
 
for(int i=0;i<size;i++)
{
	cout<<arr[i]<<" ";
}
cout<<endl;
find(arr,0,size-1);
 
getch();
}
#include<iostream.h>
#include<conio.h>


int find(int *a,int start,int end)
{


	if(start<end)
	{

		if(a[start]<a[end])
		{

		cout<<"1st Arrys condition"<<a[start]<<" "<<a[end]<<endl;
		return find(a,start+1,end);

		}
		else
		cout<<"2nd Arrys condition"<<a[start]<<" "<<a[end]<<endl;
		return find(a,start,end-1);

	}
	cout<<"Last= "<<a[end]<<endl;
}

void main()
{
clrscr();

const int size=8;
int arr[size]={7,6,13,12,2,9,5,99};

for(int i=0;i<size;i++)
{
	cout<<arr[i]<<" ";
}
cout<<endl;
find(arr,0,size-1);

getch();
}