what is wrong in my simple code

[ceeemor]

// progtam to input some integer values and get their sum.


#include <iostream>

using namespace std;

int main() {
int a[1000]; // Declare an array of 1000 ints
int n = 0; // Number of values in a.
int sum =0;

cout << " Input some positive values (for exit input a character) : " << endl;
while (n!='\n'{
sum = sum + a[n];
n++;
}
cout << "The sum of " << n << " numbers is : " << sum << endl;

return 0;
}

[helios]

'\n' just means 10. What exactly is your while condition testing?

[hidipak]

I think you want to stop when use press enter i.e. newline.

modify while loop to

while(a[n] != '\n')

[Bazzy]

'a' is an array of ints, not of chars and with the >> operator you don't read newline characters

[ceeemor]

thanks for the replies. but my code is not working. i get n as 10 always and sum - some garbage value. i want to enter some integer values and after hitting return i want to see the result to show no of entries - n and sum.

[mcleano]

Also, you're incrementing 'n' before you get user input for it so your array actually starts at a[1].

[ceeemor]

i have not recieved solution to my problem

[guestgulkan]

Well, what does your program look like now??

[HawkOfWinter]

#include <iostream>

using namespace std;

int main() 
{
	int a[1000]; // Declare an array of 1000 ints
	int n = 0; // Number of values in a.

	while (n != '\n') 
	{
		// Modify by HawkOfWinter 2009-09-12 begin
		cin >> a[n];
		n++;
		// Modify by HawkOfWinter 2009-09-12 end
	}

	int sum = 0; // Start the total sum at 0.
	for (int i=0; i<n; i++) 
	{
		sum = sum + a[i]; // Add the next element to the total
	}

	cout << n << " , " << sum << endl;

	return 0;
}

[martinlb]

An empty line (a newline) is not a numerical value, which is what cin >> a[n] expects
I would try a different exit condition, like when a 0 introduced...

while (n!=0) {

This way, if you enter a 0 the loop ends.

[gunnarstahl]

Try it with the following code.

#include <iostream>
#include <string>
#include <stdlib.h>
using namespace std;

int main() {
	int a[1000]; // Declare an array of 1000 ints
	int n = 0; // Number of values in a.

	std::string inputLine;
	bool finished = false;
	int i;
	while (!finished && n <= 1000) {
		getline(cin, inputLine);
		if (inputLine.length() == 0 || (*inputLine.c_str()) == '\n') {
			// Newline was pressed, so check if the current line is empty
			finished = true;
		} else {
			//transform the provided input into an integer
			i = atoi(inputLine.c_str());
			a[n++] = i;
			//std::cout << "Input was: " << inputLine << " - Transformed to: " << i << std::endl;
			//clearing up the input line
			inputLine = std::string();
			i = 0;
		}
	}
	int sum = 0; // Start the total sum at 0.
	for (int i = 0; i < n; i++) {
		sum = sum + a[i]; // Add the next element to the total
	}
	cout << "Number of inputs: "<< n << " - Summing up to  " << sum << endl;

	return 0;
}

Biggest difference is the use of getline() instead of the ">>" operator. And the use of atoi for transforming the input into a numeric value.

Yt,

Gunnar

[guestgulkan]

#include <iostream>
#include <string>
#include <sstream>

using namespace std;

int main()
{

  string input;
  stringstream strStream;
  
  int a[1000]; // Declare an array of 1000 ints
  int n = 0; // Number of values in a.

  getline(cin,input);
  strStream.str(input);

  while (strStream >> a[n]) //hopefully no user will type more than 1000 numbers
	{		
             n++;
	}

	int sum = 0; // Start the total sum at 0.
	for (int i=0; i<n; i++) 
	{
		sum += a[i]; // Add the next element to the total
	}

	cout << n << " , " << sum << endl;
}

[ceeemor]

thank u friends for ur positive feed backs. i am marking this topic as solved. but i want to have some modifications to my program. can any one help. pl see the new topic - modifications required