RT，代码如下。

#include<bits/stdc++.h>
#define int long long
using namespace std;
int n,t,a,mp[10010],ans;
signed main()
{
	cin >> n >> t;
	int x = pow(10,t);
	for(int i=1;i<=n;i++)cin>>a,mp[a%x]+=1;
	for(int i = 1;i <= x;i++)ans += mp[i] > 0 ? 1 : 0;
	cout << ans << endl;
	return 0;
}