Number diamond

#include <stdio.h>
#include <math.h>

int countDigits(int x){
    int count = 0;
    while(x){
        x/=10;
        count++;
    }
    return count++;
}
int main(){
    int num,nums,numsDigs,mod,div,den,j;
    while(scanf("%d",&num),num){
        if(num<100){
            printf("%d\n",num);
            continue;
        }
        int digits = countDigits(num);
        int split = (digits%2==0?digits/2:digits/2+1);
        int space = (digits%2==0?digits-1:digits);
        int bound = (digits%2==0?-1:0);
        int n = (digits%2==0?0:-1);
        for(int i=1;i<=split;i++){
            mod = pow(10,(2*i+n));
            div = pow(10,digits-(digits/2+1)) / pow(10,i-1);
            nums = num/div%mod;
            numsDigs = countDigits(nums);
            for(j=1;j<=space-(2*(i-1));j++){
                printf(" ");
            }
            for(j=1;j<=2*i+n;j++){
                den = (numsDigs>1?pow(10,numsDigs-j):1);
                printf("%d ",nums/den%10);
            }
            printf("\n");
        }
        for(int i=digits-split;i>0;i--){
            mod = pow(10,(2*i+n));
            div = pow(10,digits-(digits/2+1)) / pow(10,i-1);
            nums = num/div%mod;
            numsDigs = countDigits(nums);
            for(j=1;j<=space-(2*(i-1));j++){
                printf(" ");
            }
            for(j=1;j<=2*i+n;j++){
                den = (numsDigs>1?pow(10,numsDigs-j):1);
                printf("%d ",nums/den%10);
            }
            printf("\n");
        }
    }
    return 0;
}