Thread: Magic Box

hi

i am trying to create the magic box of 3*3 using the random function

here is my code.....

Code:

# include<stdio.h>
# include<conio.h>
main()
{
  int i,a[9];
  for(i=1;i<=9;i++)
  {
  a[i]=rand();
  }
  while (true)
  {
	if((a[0]+a[1]+a[2]==15)&&(a[3]+a[4]+a[5]==15)&&(a[6]+a[7]+a[8]==15)&&(a[0]+a[4]+a[8]==15))
	{
		for(i=0;i<9;i++)
		{
		printf("%d ",a[i]);
		printf("\n");
		}
	}
	else
	continue;

  }
}

how to use the random function of c to put the values in the array?? and when i execute it says unidentified true symbol.....wat should i do???

in case the condition is not satisfied then how should i continue so that it generates random again????
thanks

Please use code tags and properly indent your code. A few problems with your code are immediately apparent:

1. Generally, main() returns an int, but your code relies on default int and yet does not return an int.

2. You loop from i=1 to i=9, and then use i as the index for an array of 9 elements. This leads to an array index out of bounds error.

3. rand() is from <stdlib.h>, but that header is not included. Also, the pseudorandom number generator is not seeded with srand().

4. true is a C++ keyword. You either define it yourself, or you use 1 (or some other non-zero, but 1 is probably best), or use "for (;" instead of "while (1)" for your deliberate infinite loop.

Well if you used
int a[3][3];

it would be a lot simpler to write a function which summed each row and column of the array to check for whether it met the conditions for a magic square.

Salem's point is that since you are trying to represent a square matrix, a two dimensional array would be more suitable. Read the tutorial on arrays for more information.