Thread: stuck with this question

hi guyz

i hv problem with my codes of the following question:

Write a C program to receive a series of integers from the operator. Calculates the product of those integers and print the total to the screen when negative value is enter.

the output hsould be like below:

Please enter an integer: 2
Please enter an integer: 5
Please enter an integer: 4
Please enter an integer: -1
Total (product):40

i hope u can help me out with this question

thank you,

#include<stdio.h>

int main()

{
int num;
int sum;
int loop;

printf("Enter numbers:\n");




while (loop)
{
scanf("%d", &num);

sum = num * num;

if (num < 0)

printf("total: %d", sum);
}



getch();

}

Post your "codes".

First of all, what is the value of loop? Since you don't initialize it, it could be anything. You also don't have a condition for changing loop, so depending what garbage is in loop when you declare it, your while loop will either not happen at all, or be infinite.

Also, each iteration (once you get your loop working) you are overwriting the value of sum with num*num. Ie, you are not keeping a running product.

You should probably check to see if the input is negative -before- you do anything with it.

what purpose does getch() serve there?

Don't think you need to be pro to get this one

Ok:

First of all, when do you want to stop your loop? When the input is negative. So that should be your loop condition.

Secondly, if you want to keep a running product, you should read in each value, and them multiply the previous product by the value. (Not square the value that is read in like you are doing)

And third, you should only multiply your total by the new input if it is positive. (If statment, maybe?

You should initialize your variables before you start using them. That means, set them to an initial value, such as zero.

You should add a step in your < 0 check to escape from your loop. Set loop to 0, or use a break statement in there after you print your total.


Quzah.

No, the ; there splits that into two different statements, and the while loop expects only one. I would advise you to read your book's loop section over again.

Code:

for( initialize here; condition is true; change values here )
{
    do stuff here
}

Or...

Code:

do
{
    do stuff here, will happen at least once guaranteed
    you need to do any condition changes here typically
} while( condition is true );

Or...

Code:

while( condition is true )
{
    do stuff here, may not happen, depending if condition is true at the first pass
}

Quzah.

just try to complete my solution

#include<stdio.h>

int main()

{
int num=0;
int sum;

while (num >=0)
{
printf( "the first number" );
scanf("%d",&num);

Your solution should use int main(void).