该怎么去重啊

#include<bits/stdc++.h>
using namespace std;
const int N = 2e6;
int n, a[N], f[N], dp[N], ans, cnt;
int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		f[i] = 1;
		for (int j = 1; j < i; j++) {
			if (a[i] < a[j]) {
				f[i] = max(f[j] + 1, f[i]);
			}
		}
		ans = max(ans, f[i]);
		if (f[i] == 1) {
			dp[i] = 1;
		}
		for (int j = 1; j < i; j++) {
			if (a[i] < a[j]) {
				if (f[j] + 1 == f[i]) {
					dp[i] += dp[j];
				}
			}
		}
	}
	for (int i = 1; i <= n; i++) {
		if (f[i] == ans) {
			cnt += dp[i];
		}
	}
	cout << ans << " " << cnt;
	return 0;
}