adding elements in array

This is a discussion on adding elements in array within the C Programming forums, part of the General Programming Boards category; I'm making a program that will add all the values in an array to get a total value, I wrote ...

  1. #1
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    adding elements in array

    I'm making a program that will add all the values in an array to get a total value, I wrote out my program on paper and it should run just fine, but instead of the final variable of the array just getting a total value of all integers, it gets the first value of the array. Here's my program:
    Code:
    Code:
    #include <stdio.h>
    
    void main()
    
     // bcc32 -IC:\Borland\bcc55\include -LC:\Borland\bcc55\Lib register2.c  to compile
    
    
    {	
    	int	a[1000], b, c=0, d[1000], i=0,  f[1000];  // these elements are for later
    	float	e;
    
    	printf("Please enter the price of the item and hit 0 to quit:$");
    	scanf("%d", &a[i]);	
    	
    		while(a[i]!=0)
    		{
    		
    			if(i==0)
    			{
    			i++;
    			}
    		    
    		printf("Please enter the price of the item and hit 0 to quit:$");
    		scanf("%d", &a[i]);		// filling array values
    		
    		
    		
    			if(a[i]!=0)
    			{
    			a[i+1]=a[i]+a[i-1];
    			i+2;	// adding array values
    			}
    		
    		}
    			
    		
    	printf("\nThe total is $%d", a[i-1]);
    }		                                      // end program
    The second if statement is where I'm having trouble.
    When I write it out it should run like this: i=0, a[0]=1, i=1, a[1]+a[1-1]=a[1+1]
    i=3, a[3]=2, a[3+1]=a[3]+a[2] etc.

  2. #2
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    Seems like you're trying to implement a Fibonacci sequence!
    Anyway, that does "i+2" mean? If you want to increment i by 2 the way to do it is
    Code:
    i = i + 2

  3. #3
    C++ Witch laserlight's Avatar
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    A few things that will help you:
    • Indent your code properly. This will allow you to more clearly see the structure of your loops and if statements.
    • Only declare the variables that you need now. If you need variables later, add them in later.
    • Although on a technicality it is possible to argue the contrary, the main function is supposed to return an int, to declare it as such, and return 0 at the end.
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  4. #4
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    The second time your program reaches the loop header, i is 3, and a[3] is undefined at this point.
    By pure chance a[3] is 0 and the execution stops.

  5. #5
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    Thumbs up

    Quote Originally Posted by Leojeen View Post
    Seems like you're trying to implement a Fibonacci sequence!
    Anyway, that does "i+2" mean? If you want to increment i by 2 the way to do it is
    Code:
    i = i + 2
    Thanks, that fixed it!

  6. #6
    Algorithm Dissector iMalc's Avatar
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    It looks like I'm going to beat Elisia to saying it this time:

    main must return int, not void.
    My homepage
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  7. #7
    C++ Witch laserlight's Avatar
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    Quote Originally Posted by iMalc
    It looks like I'm going to beat Elisia to saying it this time:

    main must return int, not void.
    Unfortunately, you lost to me, as per post #3
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