Code seems perfect?

[adu]

Okay, basically what I have to do is find the products of X times Y, where X and Y are integers which are greater than 0 and less than 1000.
From these products find the sum of any which are palindromes.

My code which is included below seems fine with me, however I keep getting a wrong answer (393705315), I was told the correct answer is a nine digit number starting with a 5. Anything wrong with the code?

------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>

long int prod,sum;
int x,y,q,z,len;
char store[7],reverse[7];

int main() {

sum=0;

for (x=1; x<1000; x++) {
for (y=1; y<1000; y++) {
prod = x*y;
itoa(prod,store,10);
len = strlen(store);
q = 0;
for (z=(len-1); z>=0; z--) {
reverse[q] = store[z];
q++;
}
if (atoi(store) == atoi(reverse)) {
sum = sum + (x*y);
}
}

}
printf(&quot;Done. %d&quot;,sum);
getch();
return 0;
}
--------------------------------------

 

[Kirilla]

Hi.

Try this:

...
for(z=(len-1);z>=0;z--)
{
reverse[q] = store[z];
q++;
}
reverse[q] = '\0';
...

best regards,

Kirilla

 

[tchouch]

You should use for store and reverse at least 20 Bytes.

 

[Kirilla]

Hi.

The problem is starting after the first Y cycle.

When X = 1 and Y = 999
then there is 999\0 is in the store buffer and
999EEEE999 in the reverse buffer.
Because EEEE is not a number atoi translate only the number part of reverse or until \0 (NULL CHAR)
The n ext step
X = 2 and Y =1 then
there is 2\0 in the store buffer and
299EEEEE2 in the reverse buffer because NULL CHAR is not copied.
I put it manually with revese[q] = '\0'; (look above)
and it is working.

best regards,

Kirilla