Very simple question

[ok_good]

hi:

If i can use getchar() function to input some numbers from keyboard only, how i can convert or use any method to sum those numbers up? Thanks!!!

[ok_good]

also i cannot use array to hold the number..

[Tommo]

int x;
printf("Enter a number:");
scanf("%d", &x);

x now takes the value of whatever you enter.

int c;
c = getchar();
int x = c - '0';

Here, c must be between 0 and 9 inclusive. This is obviously no good.

Please read this

[ssharish2005]

int x;
printf("Enter a number:");
scanf("%d", &x);

x now takes the value of whatever you enter.

char c;
c = getchar();
int x = c - '0';

Here, c must be between 0 and 9 inclusive. This is obviously no good.

Please read this

gehchar return and int. So your char should be int to make it perfect.

ssharish2005

[Tommo]

Sorry, you are correct yes. Thanks

[foxman]

Well i'm not sure to understand what you are trying to do but you sure can recompose a number by reading one character at a time.

Somehow like this

#include <stdio.h>
#include <ctype.h>

int main()
{
	int carac;
	int nombreEntree = 0;

	printf("Enter a non negative number: ");

	carac = getchar();
	while (isdigit(carac))
	{
		nombreEntree = nombreEntree * 10 + (carac - '0');
		carac = getchar();
	}

	// Flush the input buffer if it isn't empty
	if (carac != '\n')
	{
		while (getchar() != '\n');
	}

	printf("\nThe number you entered is: %d", nombreEntree);
	getchar();

	return 0;
}

But you should make a call to scanf since scanf is good for reading number. Except in the case this was some sort of homework... whatever..

[Doriän]

...
nombreEntree = nombreEntree * 10 + (carac - '0');

Is this (and the others " - '0'"s) because getchar stores an ASCII?

[ssharish2005]

...
nombreEntree = nombreEntree * 10 + (carac - '0');

Is this (and the others " - '0'"s) because getchar stores an ASCII?

YES, Hence getchar return's and int

ssharish2005

[Doriän]

YES, Hence getchar return's and int

ssharish2005

Thanks!