B2086测试时崩溃求条

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,ans = 0,num[n]{0};
    int j = 1;
    scanf("%d", n);
    for(int i=0;i<=n - 1;i++){
		scanf("%d", num[i]);
	}
	while(j == n){
		int th = num[j] / 1000;//千位 
		int hu = (num[j] / 100) % 10;//百位 
		int te = (num[j] / 10) % 10;//十位 
		int on = num[j] % 10;//个位  
		if(on-th-hu-te > 0){
			ans++;
		}
	}
    printf("%d",ans);
	return 0;
}