Jo Number

#include <stdio.h>

int n = 500000000, i;
int arr[100000];

void swap(int* a, int* b) {
    int t = *a;
    *a = *b;
    *b = t;
}

int partition (int arr[], int low, int high) {
    int pivot = arr[high];
    int i = (low - 1);
    for (int j = low; j <= high- 1; j++) {
        if (arr[j] <= pivot) {
            i++;
            swap(&arr[i], &arr[j]);
        }
    }
    swap(&arr[i + 1], &arr[high]);
    return (i + 1);
}

void qSort(int arr[], int l, int h) {
    if (l < h) {
        int pi = partition(arr, l, h);
        qSort(arr, l, pi - 1);
        qSort(arr, pi + 1, h);
    }
}

void sJo(int div){
    arr[i++] = div;
    if(div > n){
        return;
    }else{
        return sJo(div*10+7), sJo(div*10+8);
    }
}

int main(){
    int tc;
    sJo(7);
    sJo(8);
    qSort(arr, 0, 1021);
    scanf("%d",&tc);
    for(int i=1;i<=tc;i++){
        int num;
        bool flag = false;
        scanf("%d",&num);
        if(num==7  || num==8){
            printf("Case #%d: YES\n", i);
            continue;
        }
        for(int j=0;j<1022;j++){
            if(arr[j]>num/2){
                flag = true;
                break;
            }
            if(num%arr[j]==0){
                printf("Case #%d: YES\n", i);
                break;
            }
        }
        if(flag){
            printf("Case #%d: NO\n", i);
        }
    }
    return 0;
}