dont now how to make(function call)

[shaikha]

hello !
i have problem in function call i try to do this program

A. Write a value-returning function called length() that takes a positive integer and
returns the number of digits in that integer.
B. Using the written function in part A, write a value-returning function called
isPalindrome() that checks if a positive integer is a palindrome or not. A number is
palindrome if it reads the same left to right and right to left. For example 23432 is a
palindrome, while 5675 is not palindrome. The function takes a positive integer and
returns true if the integer is a palindrome and false otherwise.
Test your functions by writing a main function that prompts the user to input an integer
and outputs its number of digits and "It Is a Palindrome" message if it is a palindrome,
otherwise "It Is not a Palindrome"

 #include<iostream>
using namespace std ;


int main (){

int n , num , sPalindrome ,length, number ;

cout<<"enter an enteger";
cin >> n ;
num=length(number);

cout<<"the number of digets is : "<< num <<endl ;


sPalindrome=bool sPalindrome ;
cout<<"It Is a Palindrome" ;
cout<<"It Is not Palindrome" ;
return 0;


}


int length(int number)
 {
    if (number < 10) {
        return 1;
    }
    int count = 0;
    while (number > 0) {
        number /= 10;
        count++;
    }
    return count;
}


bool sPalindrome()
{
	int i,temp,d,revrs=0;

	cout<<"enter the number to check :";
        cin>>i;
	temp=i;
	while(temp>0)
	{
		d=temp%10;
		temp/=10;
		revrs=revrs*10+d;

		}
	if(revrs==i)
	cout<<i<<" is palindorme";
	else
	cout<<i<<" is not palindrome";


	}

help me plzzzzz =(

[Aceix]

-Function implementations must come before main function, otherwise their prototypes.
-line 16 must be written like this: sPalindrome=sPalindrome();

For the palindrome, I will suggest you use: std::string with std::reverse(); included in the <algorithm> header.

eg:

#include <algorithm>
#include <iostream>

using namespace std;

bool checkPalindrome(string str){
  string tmp=str;
  reverse(tmp.begin(),tmp.end());
  if(
  if(str==tmp){
    return true;
  }
  return false;
}

Aceix.

[shaikha]

thank you very much
but i have error in line 11 i don't know how to write it =(

[CodeGoggles]

sPalindrome=bool sPalindrome ;

First thing you need to do is not make a variable with the exact same name as the function. This will end up confusing anyone reading your code, including yourself.

Second a function call ends with () parenthesis which contain any parameters that are specified by the declaration of the function. If none just leave the parenthesis empty.

Thirdly do not include a return type in a call to the function, the compiler gets confused and thinks you are declaring a new function.

bool isPalindr = sPalindrome() ;

looks like this.

Lastly you need a declaration of the function before the call in main.
bool sPalindrome(); // <-- a declaration

[Aceix]

As CodeGoggles said, you would want to make the variable have a different name as the function.

shaikha wrote:

but i have error in line 11 i don't know how to write it =(

Check to see if the length function is in scope(visible to the compiler before line 11). Also you could post the updated code if your problem remains unsolved.

Aceix.

[shaikha]

#include<iostream>
#include <algorithm>
#include <iostream>
using namespace std ;
bool sPalindrome=sPalindrome ;

int main (){

int n , num , sPalindrome ,length, number ;

cout<<"enter an enteger";
cin >> n ;
length=length;

cout<<"the number of digets is : "<< num <<endl ;


sPalindrome=  sPalindrome ;
cout<<"It Is a Palindrome" ;
cout<<"It Is not Palindrome" ;
return 0;


}


int length(int number)
 {
    if (number < 10) {
        return 1;
    }
    int count = 0;
    while (number > 0) {
        number /= 10;
        count++;
    }
    return count;
}



bool checkPalindrome(string str){

  if(str==reverse(str.begin(),str.end()))
  {
    return true;
  }
  return false;
}

[AbstractionAnon]

Line 5 makes no sense. You're trying to initialize a variable to itself.

You still haven't provided function prototypes for length and checkPalindrome.

Line 13 makes no sense. Again assigning a variable to itself. Did you mean to call your length function?

Line 18 makes no sense. Again assigning a variable to itself. Did you mean to call your checkPalindrome function?

Line 44: reverse returns nothing (void). You can't assign it to a string.

[Aceix]

Visit: http://www.cplusplus.com/doc/tutorial/functions/

Compare your's with this:

#include<iostream>
#include <algorithm>

using namespace std ;

//these are what I meant by function prototypes/signatures
bool checkPalindrome(string);
int length(int);

int main () {

int n,len;

cout<<"enter an enteger";
cin >> n;
len=length(n);

cout<<"the number of digits is: "<< len <<endl ;


if(checkPalindrome(to_string(n))) //requires C++11 compatible compiler for to_string() function
  cout<<"It Is a Palindrome";
else
  cout<<"It Is not Palindrome";

return 0;
}

EDIT: Don't forget the <string> header

Aceix.

[shaikha]

Aceix
thank you very muchhh <3

[shaikha]

AbstractionAnon
Line 5 makes no sense. You're trying to initialize a variable to itself.

You still haven't provided function prototypes for length and checkPalindrome.

Line 13 makes no sense. Again assigning a variable to itself. Did you mean to call your length function?

Line 18 makes no sense. Again assigning a variable to itself. Did you mean to call your checkPalindrome function?

Line 44: reverse returns nothing (void). You can't assign it to a string.


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yaah this is my problem i was taring to call the function but i don't know how