Starting with the number 1 and moving to the right in a clockwise direction a 5 by 5 spiral is formed as follows:

```
21 22 23 24 25
20 7 8 9 10
19 6 1 2 11
18 5 4 3 12
17 16 15 14 13
```

It can be verified that the sum of the numbers on the diagonals is 101.

What is the sum of the numbers on the diagonals in a 1001 by 1001 spiral formed in the same way?

## My solution

```
#include <stdio.h>
int main(){
int i,j;
int soma=1;
int inicio,diferencial;
inicio=1;
diferencial=2;
for (i=3;i<=1001;i+=2){
for (j=1;j<5;j++){
inicio+=diferencial;
soma+=inicio;
}
diferencial+=2;
}
printf("%d\n",soma);
return 0;
}
```

hugoHi, could you explain to me the logic ques you followed to make your program?