样例过了但Wrong answer on test 2

#include <bits/stdc++.h>
using namespace std;
int n, a;
int main(){
	cin >> n;
	while(n--){
		cin >> a;
		int minn = INT_MAX;
		if(a % 10 < minn && a % 10 != 0) minn = a % 10;
		if(a / 10 % 10 < minn && a / 10 % 10 != 0) minn = a / 10 % 10;
		if(a / 100 % 10 < minn && a / 100 % 10 != 0) minn = a / 100 % 10;
		if(a / 1000 % 10 < minn && a / 1000 % 10 != 0) minn = a / 1000 % 10;
		cout << minn << endl;
	}
	return 0;
}